Stephen Strasburg logged just four innings on Wednesday. (Patrick Smith/Getty Images)

The Washington Nationals know their playoff chances are slim. Their decision to trade Daniel Murphy and Matt Adams on Tuesday was reflective of that understanding. But their playoff hopes aren’t dead yet. The formula to keep them alive centers upon riding Max Scherzer and Stephen Strasburg to the finish line, giving them the one-two punch they haven’t featured since early June. Strasburg was back on the mound Wednesday night, but that ride got off to a bumpy start in Washington’s 8-7 walk-off win over the Philadelphia Phillies.

The right-hander exited after just four innings. He allowed five runs on seven hits. That alone would’ve made for a disappointing return. But Strasburg’s velocity tumbled at an alarming rate, too. Strasburg’s fastball velocity entering Wednesday averaged 95.3 mph. He usually sits 96 to 97 mph early in his starts. He was immediately off Wednesday. Instead of touching 97, Strasburg was sitting at 94 to 95 mph in the first inning. The velocity dipped precipitously by the fourth inning, when he was sitting 91 to 92 mph.

Manager Dave Martinez had Wander Suero warming up during the frame, but let Strasburg escape on his own. He threw 84 pitches. He shook his arm after several in the fourth inning. Strasburg shaking his arm alone isn’t noteworthy. He does that. But the context highlighted his apparent discomfort. After the game, however, both Martinez and Strasburg said the velocity plunge was stamina-related and he was healthy. At least healthy enough; Strasburg said doctors informed him his nerve issue could take months to dissipate. Yet there was no indication that he wouldn’t make his next start.

“He said he felt fine and I think he did get a little gassed,” Martinez said. “I thought, ‘That’s good enough for me.’ And he competed. And I’m proud of him. He went out there when we needed him and he competed.”

“I don’t really know,” Strasburg said. “I saw it too, so I’d like to think that it’s … I don’t know if it’s rust, I think it’s just endurance. Hopefully, that’s what it is.”

Strasburg returned Wednesday after having pitched just once since June 8. He first spent six weeks on the disabled list with shoulder inflammation. Then he got roughed up in a start July 20 and spent the next month on the disabled list with a cervical nerve impingement. Strasburg didn’t make a rehab start before Wednesday’s outing, but he logged several bullpen sessions and threw 77 pitches in a simulated game last week in St. Louis. The Nationals, always extra cautious with Strasburg, deemed him healthy and ready.

“He was good to go,” Martinez said. “He threw a lot of bullpens. We got him up to 75-80 pitches and he felt good.”

Strasburg admitted Washington’s precarious situation with six weeks remaining in the regular season factored into the decision to not make a rehab start.

“They asked me if I wanted a rehab assignment,” Strasburg said. “I said, ‘We’re kind of at the point of no return’. So, just got to go out there when you feel good enough to go you go, and you give everything you have.”

The club’s initial report on Strasburg’s velocity plummet — that it stemmed from him simply tiring and not an injury — is a positive. But if it turns out there’s more to it, the Nationals won’t have many options.

The drop-off from Strasburg to his replacement would be steep, and the candidates are seemingly limited. Erick Fedde and Tommy Milone would be obvious options, but neither is eligible to come off the disabled list yet. Fedde was recently transferred to the 60-day DL and isn’t available until September. Milone was placed on the 10-day DL on Tuesday, retroactive to Monday. Jefry Rodriguez, another rotation fill-in the Nationals have used this season, is already in the rotation because Jeremy Hellickson is also on the disabled list. Hellickson is eligible for reinstatement Aug. 26, but there’s no indication that he’ll be ready.

Austin Voth is the only starting pitcher in Washington’s minor league system on its 40-man roster. He surrendered seven runs in 4 1/3 innings in his only major league outing on July 14. He pitched for Class AAA Syracuse on Wednesday, allowing three runs in five innings, so he could slide into Strasburg’s rotation spot on regular rest. If the Nationals want to venture beyond the 40-man roster, they could give Phillips Valdez a shot. The 26-year-old right-hander has yet to pitch in the majors, but has a 3.23 ERA in 15 games since becoming a full-time starter with Syracuse in early June.

Regardless, the Nationals wouldn’t be able to adequately fill Strasburg’s spot. He is, when healthy, one of baseball’s most dominant pitchers. He wasn’t dominant Wednesday, but all parties claim he’s healthy. The Nationals need him to be to help keep their slim chances alive.

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