PHILADELPHIA – As the Nationals get ready for the second game of this four-game set against the Phillies, manager Davey Martinez provided some updates down on the farm at Triple-A Rochester.

Tyler Clippard begins his rehab assignment tonight with the Red Wings. The 37-year-old reliever was placed on the 15-day injured list on July 22 (retroactive to July 19) with a groin strain.

“He's gonna go and get ready, pitch down some games,” Martinez said of Clippard. “The biggest thing for me is, as we always talk about, is back-to-back days. We want him to be able to pitch two innings like he did when he came up here. So we got to see him do that. I know we're kind of in a different position, but you never know when it comes to the bullpen help. We always want to keep guys and if he's pitching well.”

The right-hander only pitched in one game with the Nationals after finally getting the call from Rochester. He pitched two scoreless innings against the Braves on July 14, his first appearances as a National since 2014. Clippard made 33 appearances with the Red Wings this year, going 4-1 with a 2.48 ERA and 1.211 WHIP.

Once healthy, Martinez envisions Clippard helping out at the major league level again.

After fielding questions for several minutes late Sunday afternoon about the Nationals’ 9-3 victory over the Phillies, Davey Martinez was asked how he would sum up the entire 14-games-in-13-days stretch that had finally concluded.

“I can’t wait for the off-day tomorrow,” he said with a smile.

He wasn’t alone. The entire Nationals organization had been counting down the hours to their first day off in two weeks. (The last one came on June 6, in between series in Cincinnati and Miami, if you can remember that far back.)

How’d they do during that 14-game stretch? Not well. They went 3-11, with an eight-game losing streak in there, and were outscored 91-59. They lost Stephen Strasburg to a rib injury and Josiah Gray to a rain delay. They made 21 transactions, bringing three pitchers up to D.C. for the first time: Jackson Tetreault, Reed Garrett and Cory Abbott. They activated Strasburg off the IL and placed him back on the IL. They both recalled and optioned Sam Clay, Joan Adon, Andres Machado and Abbott during that time.

The day off was desperately needed, especially for the pitching staff. Now, though, Martinez has the ability to hit the reset button and align his starters as he prefers.

The Nationals formally placed Stephen Strasburg on the 15-day injured list today with a stress reaction of his second and third ribs, a diagnosis that doesn’t necessarily offer an optimistic or pessimistic outlook on the right-hander’s timetable to return but is related to the thoracic outlet surgery he had last summer and ensures he’ll be out for a not-insignificant period of time while letting this latest injury heal.

Strasburg is scheduled to fly to Southern California to be examined by specialist Neal ElAttrache, the noted orthopedist who just performed teammate Joe Ross’ second Tommy John surgery last week.

“This surgery, you just don’t know where it’s going to go,” Martinez said of pitchers who have attempted to return from thoracic outlet surgery. “I’ve seen a lot of guys go through this and not come out of it good right away. I’ve seen guys come out of it where they pitch for many years. We’re just going to have to wait. There’s no timeline right now for Stephen. He’s going to go see another specialist, and then we’ll know more.”

Strasburg had just completed a yearlong rehab process from last summer’s career-altering surgery, making his return to a big league mound Thursday night in Miami. Though he gave up seven runs in 4 2/3 innings, with a fastball velocity that averaged 90-91 mph, the 33-year-old was genuinely encouraged with how he felt physically and was prepared to make his next start in five days.

But during a standard bullpen session Saturday, Strasburg noted something didn’t feel right. And on Sunday, shortly after the Nationals announced him as their scheduled starter for tonight’s game against the Braves, he informed the club of this new bout of discomfort, leading to an MRI on Monday.

MIAMI – Hello from what used to be called Marlins Park and what used to house the Home Run Thingamabob. Neither is true anymore, which is quite a pity. The Nationals make their second trip here to South Florida in three weeks, hoping for a series win this time after dropping two of three to the Marlins last month.

The Nats enter this series with some positive momentum after taking three straight from the Reds over the weekend. A victory tonight would give them their first four-game winning streak of the season, which would certainly be a welcome development.

It’s Joan Adon on the mound for the opener. The rookie faced the Marlins here last month and had success, allowing only one run over 4 2/3 innings, albeit with a hefty pitch count of 84 in what wound up a 5-1 loss. The kid has been better, allowing three or fewer runs in five of his last six starts and reaching the sixth inning in each of his last two outings. He’s still seeking his first win since April 19, though. It’s been a while.

Rookie Edward Cabrera starts for Miami, having tossed six innings of one-hit ball against the Rockies in his season debut last week. The right-hander made his major league debut against the Nats last season, allowing three runs over 6 1/3 innings.

Some transactions to share: Utility man Ehire Adrianza, finally eligible to come off the 60-day injured list after straining his quadriceps in late March, has been activated. Fellow utility man Dee Strange-Gordon has returned from paternity leave. They’ll take the roster spots of reliever Victor Arano, who has been placed on the 15-day IL with left knee inflammation, and infielder Lucius Fox, who was optioned back to Triple-A Rochester after spending a couple days on the roster in Cincinnati without appearing in a game.

CINCINNATI – It’s a lovely Sunday in The Queen City as the Nationals look to win this four-game series against the hosting Reds.

With the early game today, a flight to catch tonight and an off-day tomorrow before a series against the Marlins in Miami gets underway Tuesday night, there wasn’t a whole lot of news coming out of the Nats clubhouse this morning. So let’s go through some notes before we get underway one last time in Cincinnati …

* Here’s your daily non-update Stephen Strasburg update: He did some work in the visitors' bullpen at Great American Ball Park this morning as part of his routine while recovering from last summer’s thoracic outlet surgery and Friday’s rehab start with Triple-A Rochester, in which he pitched six shutout innings on 83 pitches. Pitching coach Jim Hickey and others were working with Strasburg.

Although things seem to be going well for the veteran right-hander and his season debut should be coming soon, manager Davey Martinez isn’t ready to commit to anything until Strasburg goes through his bullpen session tomorrow with the team in Miami.

“He's had a routine that he does in between starts, so he's just doing his routine,” Martinez said of Strasburg’s work this morning during his pregame media session. “And he's gonna throw a bullpen here in the next day. We'll see where he's at and we'll have a conversation after the bullpen. But so far, everything looks good. I don't want to make any decisions yet 'til he throws his bullpen and we go from there.”

CINCINNATI – There was a good amount of pregame news ahead of the Nationals’ second game against the Reds at Great American Ball Park. Some were baseball related. Some were more important than baseball.

Starting on the diamond, the Nationals made a handful of roster moves before today’s game. They recalled right-hander Andres Machado from Triple-A Rochester and placed left-hander Josh Rogers on the 15-day injured list with a left shoulder impingement, leaving no lefties in the bullpen for tonight.

Machado rejoins the Nats for his third stint this season, in which he has a 5.40 ERA with 10 strikeouts and seven walks in 12 appearances. Rogers has a 5.13 ERA in 16 games (three starts) with the Nats and was charged with two runs after serving up a three-run home run to Kyle Farmer while only recording two outs last night.

“He went on the IL with a little bit of impingement in his left shoulder. So we'll see,” manager Davey Martinez said during his pregame media session. “He's gonna get an MRI tomorrow and we'll see how he's doing tomorrow. But we brought in Machado to fill that void as well.”

Martinez mentioned yesterday that lefty Evan Lee could be used out of the ‘pen on his bullpen day, but that isn’t until tomorrow. So how will the skipper use his relievers without a southpaw?

CINCINNATI – Surely the Nationals offense will break out of its funk and score some runs tonight, right?

Since their 6-5 win over the Rockies on Sunday – their fourth victory of their previous five games – the Nats have been outscored 36-6 in four straight losses this week.

They’ll get their shot at 10-year veteran Mike Minor on Friday at Great American Ball Park. The 34-year-old is making his Reds debut after being acquired from the Royals for Amir Garrett in March. Minor is 3-3 with a 4.47 ERA in 11 career starts against the Nationals, all of which came between 2010 and 2014, when he was with the Braves.

The Nats have been kept quiet by right-handed starting pitchers this week, so maybe facing a lefty will bring different results. They do have a slightly better average against southpaws this year, hitting .253 to rank fifth in the National League.

Josiah Gray will get to face the team that selected him in the second round of the 2018 First-Year Player Draft for the first time. The young right-hander didn’t fare so well when he faced his other former team, the Dodgers, for the first time last week, giving up seven runs in just three innings of work. After the game, Gray said he let his emotions get the best of him, but was looking forward to facing the Reds for the first time. We’ll see if he can keep his emotions in check tonight.

Reds shortstop Kyle Farmer (not in tonight’s lineup after going 2-for-4 with a three-run home run last night) arrived in Cincinnati in the trade that sent Gray to Los Angeles in December 2018. They are the only two major league players currently active from that six-player deal.

The Nationals have recalled Andres Machado from Triple-A Rochester and placed Josh Rogers on the 15-day injured list with a left shoulder impingement. So manager Davey Martinez has no left-handers in his bullpen tonight, with Evan Lee’s bullpen day not until tomorrow.

Congratulations to Dee Strange-Gordon and his wife, Jojo, who welcomed the couple’s second child this morning. They named their son Dash, a fitting name for the son of a speedy utility player. Former Nationals speedster Trea Turner also used “Dash” as a nickname for his firstborn son, Beckham.

The Nationals will place Strange-Gordon on the paternity list and will make another roster move this afternoon.

WASHINGTON NATIONALS at CINCINNATI REDS
Where: Great American Ball Park
Gametime: 6:40 p.m. EDT
TV: MASN, MLB.tv
Radio: 106.7 The Fan, MLB.com
Weather: Mostly sunny, 79 degrees, wind 6 mph out to left-center field

NATIONALS
2B Cesár Hernández
LF Lane Thomas
RF Juan Soto
DH Nelson Cruz
1B Josh Bell
3B Maikel Franco
C Riley Adams
SS Luis García
CF Victor Robles

RHP Josiah Gray

REDS
CF Nick Senzel
3B Brandon Drury
LF Tommy Pham
1B Joey Votto
C Tyler Stephenson
DH Mike Moustakas
RF Albert Almora Jr.
2B Alejo Lopez
SS Matt Reynolds

LHP Mike Minor

NEW YORK – Mike Rizzo was discussing the Nationals’ ragged opening two months to this season about an hour before first pitch of today’s series finale at Citi Field and on multiple occasions singled out his team’s poor fundamentals for making life even more difficult than it already is on a struggling pitching staff and lineup.

“We’re a team that the margin for error is small,” the longtime general manager said. “We can’t be giving extra outs on defense, and running into outs on the basepaths. To me, walks and errors have been the Achilles’ heel of the start.”

By day’s end, Rizzo had seen that very scenario play out and contribute to yet another loss. The Nats’ 5-0 defeat at the hands of the Mets, completing a three-game sweep, perhaps was inevitable regardless because the lineup was shut out for the second straight day and has now gone 21 consecutive innings without scoring a run. But it’s also not inaccurate to say four of the five runs they surrendered were a direct result of shaky defense and two of the five walks their pitching staff issued.

"The walks and the defense: Two bad combinations," manager Davey Martinez said. "We've got to play better on defense,and we've got to limit the walks. I've always said the hitting comes and goes. That's part of the game. But you've got to do three constants: Play defense, run the bases well and pitch well. And today, two of the three things we didn't do well."

This team, as Rizzo noted, simply can’t afford to make fundamental mistakes because it simply doesn’t have enough consistent offensive firepower or an accomplished enough pitching staff to make up for it. Perhaps it could’ve been overlooked today, but only if they had produced at the plate to offset the other stuff.

The Nationals haven’t won a series opener since May 3, more than three weeks ago at this point. Their opponent that evening: The Rockies, with Germán Márquez on the mound for a 10-2 victory. Guess who’s in town for a four-game series beginning tonight? And guess who’s on the mound?

Yep, the Nats will try to duplicate that earlier feat against Márquez and the Rockies, who after a surprising start to the season have lost 12 of their last 16. Following a brutal stretch against some really tough competition, the Nationals will hope to take advantage of a more favorable matchup this weekend.

The lineup again features Keibert Ruiz in the No. 2 spot, ahead of the struggling Juan Soto and the surging Nelson Cruz. It also includes Dee Strange-Gordon at shortstop for the fourth time in six games, an interesting development.

Patrick Corbin gets the start, and he likewise will be looking to duplicate his performance the last time he faced the Rockies. One night after that series-opening win at Coors Field, Corbin tossed a complete game, allowing five runs (three earned) all in the bottom of the fourth and posting zeros the rest of the way during a 5-2 loss.

COLORADO ROCKIES at WASHINGTON NATIONALS
Where: Nationals Park
Gametime: 7:05 p.m. EDT
TV: MASN, MLB.tv
Radio: 106.7 FM, MLB.com
Weather: Cloudy, 74 degrees, wind 9 mph out to left field

As the Nationals look to win their first home series of the 2022 season, they will once again be without shortstop Alcides Escobar, who will miss his third straight game.

Escobar was a late scratch from the starting lineup before Tuesday’s series opener against the Mets. After the game it was revealed he was dealing with an infection under the nail of his left index finger.

The timing of the infection was unfortunate for the veteran infielder. After a slow start to the season in which he was batting only .127 over his first 17 games, Escobar has slashed .440/.482/.560 with a 1.042 OPS over his last seven outings, going 11-for-25 with three runs scored, a double, a triple, a walk and a hit-by-pitch. However, his struggles in the field continued as he committed four errors over that seven-game span.

The 35-year-old tried to convince manager Davey Martinez he could swing the bat without using the affected finger (a la Trea Turner from a couple of years ago), but the skipper didn’t want to risk it.

Doctors removed fluid from the finger on Wednesday, but it remained sore, keeping Escobar out of the lineup for the Nats’ 8-3 win. He then woke up Thursday morning feeling a lot better, with Martinez expecting the shortstop to return for Friday’s series opener against the Astros after one more off-day.

Almost halfway through this six-game homestand, the Nationals need to win this afternoon to earn a series victory against the Mets before the Astros come to town this weekend.

In the four home series before this one, the Nationals went 0-3-1, with the one tie coming in a four-game series three weeks ago in which they won the first two games against the Diamondbacks before dropping the last two.

Joan Adon looks to give the Nats an opportunity to win just their fifth home game of the season. The 23-year-old right-hander is 1-5 with a 6.99 ERA and coming off an outing in which he struck out a season-high six batters against the Angels. 

Adon faced this Mets squad in his season debut on April 9, giving up four runs on four hits and four walks while striking out three over 4 1/3 innings in a 5-0 loss.

Right-hander Taijuan Walker makes his fourth start for the Mets this season and first that won’t come against the Phillies. The 29-year-old is 0-0 with a 4.91 ERA over 11 innings in his three outings against Philadelphia. The Mets went 1-2 in those games, but the one victory came a week ago after Walker gave up seven runs (six earned) and nine hits in just four innings only to watch the Phillies bullpen completely implode while giving up seven runs in the ninth for an 8-7 Mets win.

Stephen Strasburg and Joe Ross each made it through the first simulated games of their rehab programs strong and are prepared to go through that drill again this weekend.

Strasburg and Ross pitched in those game situations Monday at the Nationals’ spring training complex in West Palm Beach, Fla. Davey Martinez didn’t have details on the number of innings or pitches each threw, but the manager had previously said they were scheduled for two innings a piece.

“What I got was: They both felt good,” Martinez said, relaying information he received from the organization’s medical staff. “So that’s good.”

This was a key step for both right-handers in their return from injury-plagued 2021 seasons. Strasburg, who had thoracic outlet surgery last July, and Ross, who was shut down last summer with a partially torn elbow ligament and then had surgery in March to remove a bone spur, had previously only thrown live batting practice.

The simulated game allowed both righties to pitch in a situation that more closely resembles a real game. Facing teammates who are also rehabbing in Florida, they would typically throw about 15 pitches per “inning,” then return to the dugout to rest for 10-15 minutes before taking the mound for their second “inning” of work.

The Nationals have been playing better baseball, getting much better starting pitching. That hasn’t necessarily translated into a lot of wins, though. After going 3-1 to start their recent West Coast trip, they’ve gone 1-5 since entering tonight’s game against the Mets.

Aaron Sanchez gets the ball for his fourth start as a member of the rotation. All three previous outings have come against National League West opponents (the Giants twice, the Rockies once). Sanchez has his work cut for him in a Mets lineup that ranks first in the league in hits and on-base percentage and fourth in runs scored and OPS.

The Nats also have their work cut out facing right-hander Tylor Megill, who has been surprisingly dominant so far. Megill, you’ll remember, was the emergency opening day starter after both Jacob deGrom and Max Scherzer were unavailable, and he proceeded to shut them out over five innings.

Alcides Escobar remains out after being scratched from last night's lineup with an infection under his left pointer finger nail. Dee Strange-Gordon is back playing shortstop and batting eighth.

NEW YORK METS at WASHINGTON NATIONALS
Where: Nationals Park
Gametime: 7:05 p.m. EDT
TV: MASN, MLB.tv
Radio: The Team 980, MLB.com
Weather: Mostly cloudy, 66 degrees, wind 9 mph in from right field

The Nationals had noticed how well Carl Edwards Jr. was pitching at Triple-A Rochester for several weeks now. Eventually, it got to the point where they felt there was no reason to wait any longer, so this afternoon they called up the 30-year-old and added his experience to their bullpen.

Edwards, owner of a 3.77 ERA and 1.138 WHIP in 206 career big league appearances, had his contract purchased. Fellow right-hander Andres Machado was optioned to Rochester to open a spot on the 26-man roster, with Mason Thompson transferred to the 60-day injured list to clear a spot on the 40-man roster.

In 13 games at Triple-A, Edwards was utterly dominant. His ERA was 0.63, with only one run allowed in 14 1/3 innings. He surrendered only three hits while walking four and striking out 17. There was nothing not to like about that performance.

“Carl was really throwing the ball well,” manager Davey Martinez said. “I spoke to (Rochester manager) Matt LeCroy, and we thought it was time to get him up here. He did everything we asked him to do. He checked all the boxes, and I think he can help us here.”

Martinez knows Edwards well, having both been employed by the Cubs before. From his debut in 2015 through 2018, Edwards posted a 3.06 ERA and 1.069 WHIP over 172 games. He also made 15 postseason appearances over the years, including eight during Chicago’s historic 2016 World Series run. (Though around here he’s perhaps best known for giving up a towering home run to Bryce Harper during the 2017 National League Division Series.)

ANAHEIM, Calif. – Dee Strange-Gordon made the Nationals’ opening day roster because of his ability to get on base, his ability to wreak havoc once he’s on base and his ability to play a multitude of positions.

Tonight, Strange-Gordon is needed most at a new position. With struggling starter Alcides Escobar sitting on the bench, he finds himself in the lineup and at shortstop for the first time this season.

“I wanted to get him in there,” manager Davey Martinez said. “It’s been a good matchup for him. He’s been taking a lot of ground balls. On his rehab assignment, we had him play shortstop and he looked good. So I wanted to get him out there today.”

Strange-Gordon hasn’t played shortstop yet for the Nationals, but as Martinez noted, he did make several appearances there during his rehab stint with Triple-A Rochester while recovering from the undisclosed illness that left him on the injury list for 2 1/2 weeks.

The 34-year-old does have considerable experience at shortstop during his career, having first come up with the Dodgers at that position before shifting to second base and more recently learning his trade in the outfield.

DENVER – Nelson Cruz is out of the Nationals lineup for the second straight day, though manager Davey Martinez said the 41-year-old designated hitter’s lower back is feeling better.

Cruz hasn’t played since Lane Thomas pinch-hit for him in the seventh inning of Tuesday night’s series opener against the Rockies, hampered by lower back stiffness. He sat out Wednesday night’s game, only the second time he hasn’t been in the lineup this season.

Martinez said Cruz suggested he could have started today’s series finale, but the manager didn’t want to take a chance of him needing to depart early again, given the fact he only has three players on his bench at the moment.

“We’re at the point now where if we utilize him as a pinch-hitter, as far as just getting him out there, it’s great,” Martinez said. “I don’t want him to stiffen up during the game. So we thought we’d give him another day. For me, especially with our bench only being a couple guys, if we can use him later in the game, instead of putting him in and something happens … hopefully he’ll be in there tomorrow.”

Cruz has been mired in a season-long slump, entering the day with a .143 batting average and .442 OPS (both second-worst among qualified National League hitters).

DENVER – Nineteen days have passed since Dee Strange-Gordon first was sent back to his hotel in Pittsburgh with an illness, then late sent back to Washington with instructions not to leave his home until he was medically cleared to do so.

All the veteran utilityman could do throughout the process was some agility workouts with large rubber bands, then use a virtual reality system to watch major league pitchers throw various pitches toward him. Otherwise, he couldn’t pick up a bat, couldn’t play catch, couldn’t come to the ballpark for workouts.

“Just part of it,” he said today. “That’s how the world works right now. I had to do what I had to do. I’m just thankful I didn’t get anybody else sick.”

Strange-Gordon did not get anybody else sick, and today he finally was activated off the injured list and reinstated to the Nationals’ active roster for the opener of their three-game series against the Rockies.

“It’s been a while,” he said. “Happy to see my teammates. Happy to be back.”

DENVER – The Nationals lineup just scored 28 runs over the weekend in pitcher-friendly Oracle Park. How many will they score over the next three nights at Coors Field, the greatest hitter-friendly park in major league history? The Nats haven’t hit for much power all season, even in San Francisco. So the thin air may not help them as much as the huge outfield dimensions here might.  

Davey Martinez will hope he can keep Josh Bell, Yadiel Hernandez and Victor Robles hot. He’ll also hope Juan Soto, Nelson Cruz and Keibert Ruiz can get going and start contributing on a more consistent basis. They’ll face Rockies right-hander Germán Márquez, who enters with a 5.57 ERA but has enjoyed success against the two Nationals he’s faced the most in his career: Bell (1-for-18 with a homer) and César Hernández (1-for-11).

Erick Fedde gets the start for the Nats; he was effective last time out against the Marlins, allowing only two runs on three hits. But he lasted only 4 2/3 innings because his pitch count was a whopping 91. He’s got to figure out how to finish off hitters once he gets ahead in the count and avoid those long at-bats that keep killing him.

The Nationals announced they have returned from rehab assignment and reinstated Dee Strange-Gordon, optioned Lucius Fox to Triple-A Rochester and transferred Aníbal Sánchez to the 60-day injured list.

WASHINGTON NATIONALS at COLORADO ROCKIES
Where: Coors Field
Gametime: 8:40 p.m. EDT
TV: MASN2, MLB.tv
Radio: 106.7 The Fan, MLB.com
Weather: Mostly cloudy, 61 degrees, wind 10 mph in from left field

Twelve days after first getting ill and being forced to isolate in his Pittsburgh hotel, Nationals utilityman Dee Strange-Gordon will begin a rehab assignment with Triple-A Rochester.

Strange-Gordon is leading off and playing shortstop for the Red Wings, his first competitive game since he served as a last-ditch relief pitcher during an April 12 loss in Atlanta. Two days later, he was supposed to be in the Nats lineup for their series opener against the Pirates, but was sent back to the team hotel with an illness that has never been officially disclosed by the club.

The Nationals placed Strange-Gordon on an unspecified injured list the following day, one that removed him from the organization’s 40-man roster, which has been the fate for other players who tested positive for COVID-19 over the last two seasons. He was allowed to drive himself home to D.C. a couple of days later, but remained in quarantine until recently.

Because of that time off with no ability to work out, Strange-Gordon is going to need some time to get himself back into playing shape again. He was at Nationals Park on Monday for a workout, and manager Davey Martinez said “he got tired pretty quickly.”

“He didn’t do much (while quarantined),” Martinez said. “With him, he’s built for speed and putting the ball in play, stuff like that. We’re going to get him to play some outfield, some middle infield while he’s down there. I’ll stay in touch with (Rochester manager Matt LeCroy) and see how he’s doing every day. I talked to Dee and I told him: ‘When you feel like you’re ready, just let us know and we’ll keep eyes on you.’ ”

The Nationals were relieved to learn Josh Bell could return to today’s lineup after departing Wednesday night’s game with tightness in his left knee. They were not so relieved to learn another member of their bullpen is out with an arm ailment.

The Nats placed Hunter Harvey on the 10-day injured list shortly before today’s series finale against the Diamondbacks with a right pronator strain, a situation that appears to have just emerged within the last 24 hours after the hard-throwing reliever tossed a scoreless inning.

Harvey, the former Orioles first-round pick whose career has been beset by a smorgasbord of injuries, made four scoreless appearances since joining the Nationals bullpen during the season’s opening weekend. The 27-year-old was starting to earn his way into manager Davey Martinez’s good graces and perhaps start getting called upon in high-leverage situations, but something apparently didn’t feel right during Wednesday night’s game.

Harvey entered that outing averaging 97 mph on his fastball in his first three appearances. That number went down to 96 mph during Wednesday’s game, bottoming out at 94.3 mph on one of the 12 pitches he threw to three Arizona batters.

The pronator is part of the flexor mass group of muscles and tendons in the forearm, near the elbow. A pronator strain would be to one of the muscles in that area, not an uncommon injury for pitchers.