This afternoon, Stephen Strasburg threw a bullpen session, and according to Matt Williams, he had no "issue[s] with his upper back". While that would seemingly give him the all clear to start Friday against the Braves, the Nationals will instead hold him back so that he can face the Mets on Wednesday.
"If Strasburg skips one start and returns to the rotation in his normal spot, he would start the series finale against the Mets on Wednesday. As a result, the Nationals rotation against the Mets would remain, in order: Max Scherzer, Jordan Zimmermann and Strasburg."
Washington is currently 6.5 games behind New York for the lead in the NL East, and their upcoming series has the potential to either save their season, or seemingly put the nail in the coffin. Lining up Strasburg, along with Scherzer, and Zimmermann will give them the best shot at moving up in the standings; which they desperately need to do.
A sweep could propel the Nationals within two or three games of the Mets, but losing the series could put them eight or nine back with 23 games left to play. While their playoff hopes won't be completely decided by how they perform against New York, it will undoubtedly define how hard it will be for them as the season winds down.
If they can manage to take the series, and gain ground in the standings, the Nationals could pave the way for an incredibly dramatic finish to the year. Their final series is a three-game set against the Mets, and the NL East could potentially be up for grabs.