Stephen Strasburg could pitch for the Nationals on Tuesday. (Alex Brandon/AP)

Stephen Strasburg will pitch in a baseball game Tuesday. Whether it’s for the Washington Nationals against the Philadelphia Phillies or for one of the Nationals’ minor league affiliates remains undecided, Manager Dave Martinez said Saturday.

Martinez spoke shortly after Strasburg completed a bullpen session at muggy Nationals Park. The right-hander reported feeling good immediately after the session, but the club will wait until at least Sunday before determining his next step.

“He threw the ball really well, threw like 42, 43 pitches and felt really good. Once again, we’ll figure out how he feels tomorrow and we’ll go from there,” Martinez said. “We’ll talk to him tomorrow. We don’t know if it’s Tuesday here or Tuesday in a rehab stint. We don’t know that yet; we’ll figure that out tomorrow.”

The 30-year-old Strasburg has not pitched since July 20, when he made a start after six weeks on the disabled list with shoulder inflammation. He was placed on the DL again five days later, this time with a cervical nerve impingement in his neck that had been bothering him since spring training. He received an injection July 27 and resumed throwing four days later.

He has since thrown a few bullpen sessions, and he tossed a simulated game this week in St. Louis. The Nationals typically take the conservative route with Strasburg’s injuries, but their dire situation — they were seven games out of first place entering Saturday — may prompt them to take a more aggressive approach and bypass a rehab start.

If they don’t, the Nationals will need a starter Tuesday because Jeremy Hellickson, who would have been on turn for the start, was placed on the disabled list Saturday. Tommy Milone was moved to the bullpen and is an option if he isn’t needed for extensive work Saturday or Sunday. If he is, Washington will need to look elsewhere and perhaps call up Austin Voth from Class AAA Syracuse. Voth last pitched Thursday, which would put him on turn to pitch Tuesday on normal rest.

But the Nationals would rather avoid depending on Voth, who allowed seven runs across 4 1/3 innings in his only major league start, in such a pivotal game. Tuesday marks the start of a critical three-game set against the Phillies, one of the two teams the Nationals are chasing in the National League East. Philadelphia entered Saturday a half-game behind the first-place Atlanta Braves and 6 1/2 games ahead of Washington. The Nationals and Phillies have nine meetings remaining. Strasburg, who has a 3.90 ERA in 14 starts, has yet to face Philadelphia this season.

Herrera nearing return, too

Kelvin Herrera could join Strasburg in coming off the disabled list when the Phillies are in town. The reliever threw a 15-pitch simulated game Saturday and emerged healthy. Martinez said Herrera, who has been on the disabled list since Aug. 8 with shoulder inflammation, could come off the DL on Tuesday or Wednesday.

“We wanted him to face hitters,” Martinez said. “He was going to throw a bullpen today, and I wanted him to face a couple hitters just to zone in a little bit and see where he’s at. He came out of it really good; he said he was feeling good.”

When Herrera returns, he will probably slide in as the closer, bumping Koda Glover to a setup role. Sean Doolittle, Washington’s original closer, threw a bullpen session Friday. Martinez reported his left foot was sore afterward but his arm felt “great.” Doolittle is scheduled to throw another bullpen session before any other steps are taken.

“He’s another guy, because he’s in the back end of the bullpen, maybe a sim game when he’s ready will be sufficient,” Martinez said.

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