Sean Doolittle has a pinched nerve in his left foot. (Jonathan Newton/The Washington Post)

PITTSBURGH — Sean Doolittle’s disappointment was obvious as he limped across the visitors’ clubhouse at PNC Park on Tuesday afternoon, so Brandon Kintzler made his way over to his bullpen partner and gave him a hug. They laughed as a group formed around his locker. Then Doolittle looked down at the walking boot that was just placed around his left foot.

“Is this a little dramatic?” the Washington Nationals’ all-star closer asked to more laughs.

The walking boot was necessary because the pain in Doolittle’s left foot, between the big and second toes, had intensified over the previous 24 hours after surfacing Friday. He found out he had a neuroma — doctor talk for pinched nerve — there and the only remedy was rest. Left without a choice, the Nationals placed Doolittle on the 10-day disabled list retroactive to July 7, striking another blow to the middling club and making him ineligible for next week’s All-Star Game in Washington. Doolittle was named to his second all-star team Sunday after pitching to a 1.45 ERA and compiling 22 saves in 35 games this season.

“The all-star stuff is kind of secondary right now,” the 31-year-old Doolittle said. “I think I’ll still be able to participate in the peripheral stuff. And I’m still excited about being a part of it in the home city. Yeah, it’s a bummer, but I want to be back for the guys.”

In addition, Washington optioned right-hander Jefry Rodriguez to Class AAA Syracuse. The club recalled right-handers Wander Suero and Austin Voth to take the two spots on the roster.

Doolittle explained that he’s always dealt with some pain in the area every spring training, but it’s minimal and dissipates quickly — nothing like the discomfort he’s experienced in recent days. He said the problem initially surfaced when he jogged out to the bullpen at Nationals Park on Friday and it worsened. He pitched through it, tossing a perfect inning, but his mobility was hampered and he hasn’t pitched since.

Doolittle was rendered unavailable over the next two days as the Nationals bullpen assumed a huge burden. He then threw a bullpen session and did some fielding drills Monday to push it. He needed to answer whether he could be available immediately. The answer was a resounding no. Nationals Manager Dave Martinez said Kelvin Herrera, acquired last month after excelling as the Kansas City Royals’ closer, will assume ninth-inning duties until Doolittle returns.

“Throwing off the mound felt okay,” Doolittle said. “I couldn’t quite get into my mechanics the way I wanted to, as far as the way I use my lower body. The ball was coming out of my hand okay, but I had no mobility running. Moving side to side was a pretty big issue. I think now it was really sore after the fact. I kind of aggravated it. And today it was obvious it didn’t respond well, it didn’t pass that test.”

The left-hander arrived in Washington last July with injury concerns, but not of this variety. Shoulder injuries had plagued his career with the Oakland Athletics, but that was it over the previous four seasons. The problem area hasn’t flared up since joining the Nationals. That history, however, informed Doolittle and the team’s decision: A foot injury could lead to compensating for it, which usually leads to altered mechanics, which typically increases the odds of an arm injury.

“The good news is I can play catch,” Doolittle said. “And I’ve got this stupid thing on to let it calm down for a couple days. I can still play catch, keep my arm in shape. So as soon as it clears up, hopefully, it won’t be that long of a process. But unfortunately, it’s kind of symptomatic right now, based on what I can tolerate. There’s not like a timetable we can set. So it’s really frustrating.”

The 24-year-old Rodriguez was sent back to the minors after allowing six runs in five innings against the Pirates on Monday. By optioning Rodriguez, the Nationals gave themselves an extra arm for a bullpen that is running on fumes. Suero is strictly a reliever, but Voth is a starter who could provide length if necessary. If he isn’t needed out of the bullpen, the Nationals could have him start Saturday against the New York Mets. That would have been Rodriguez’s turn.

Suero, 26, returns to the Nationals after posting a 3.63 ERA in 15 appearances for them earlier this season. The 26-year-old Voth, meanwhile, has been called up three this season but hasn’t yet made his major league debut. He has a 3.55 ERA in 15 starts for Syracuse this season. In his last seven starts, Voth tallied a 2.18 ERA across 45 1/3 innings.

NATIONALS (45-45)
Adam Eaton RF
Juan Soto LF
Anthony Rendon 3B
Bryce Harper CF
Matt Adams 1B
Trea Turner SS
Daniel Murphy 2B
Spencer Kieboom C
Jeremy Hellickson P

PIRATES (42-48)
Corey Dickerson LF
Starling Marte CF
Gregory Polanco RF
Colin Moran 3B
Elias Diaz C
Josh Bell 1B
Jordy Mercer SS
Max Moroff 2B
Joe Musgrove P

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