Stephen Strasburg scratched from Thursday's game vs. Marlins

Nationals pitcher Stephen Strasburg was scratched for Thursday's game vs. the Marlins, a reversal of the decision manager Davey Johnson made on Tuesday when he said the right-hander will play Sept. 19. (David Banks/Getty Images)

Washington Nationals pitcher Stephen Strasburg has been scratched from Thursday's home game against the Miami Marlins, continuing the concern over the 25-year-old flamethrower's forearm soreness.

The decision to shelve Strasburg comes as a setback after manager Davey Johnson said Monday that the right-hander was ready to go. Strasburg was scratched from Friday's game against the Philadelphia Phillies because of forearm soreness. He missed the end of the 2010 season and all of the 2011 season while recovering from Tommy John surgery.

Johnson said on Monday, after Strasburg participated in a bullpen session, that he looked good and reported no complications with his arm and said he would start on Sept. 19.

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According to a report Thursday from Mark Zuckerman of CSNWashington, the soreness hasn't subsided in the way Johnson had initially thought, and it became apparent Wednesday when Strasburg was warming up, trying to get loose before a catch. Johnson said it was his decision to sit him:

"It’s just not worth the risks. He wanted to go tomorrow, I said no....He came in, they tested him, everything was fine. He wanted to go. But in my book, I don’t want to have anything bothering you the day before you pitch."

In his place, Gio Gonzalez will get the start on Thursday -- his 28th birthday -- to kick off the series against the Marlins. Jordan Zimmermann will get the start for Friday's game, and then Strasburg will be evaluated for a possible appearance Saturday night. The Nationals close out the series on Sunday afternoon.

Strasburg admitted in the report he doesn't know what's causing the chronic soreness and tightness in his forearm but added that the problem is simply getting loose because he feels fine once he's actually ready to pitch. He said the team doctor didn't see anything structurally wrong with his arm and at this point is just taking it day-to-day:

"I don’t know what’s going on, but I think it works better for the club. Instead of going out there and potentially have it happen to me during a game, give it a couple extra days, let Gio and Jordan go ahead, get it done and get out there on Saturday ... I wouldn’t say I’m too concerned, because when I get nice and loose it feels 100 percent. The tough thing is getting loose ... I did all the tests. [Team medical director] Wiemi [Douoguih] looked it over, and everything is structurally sound. I think it’s just part of it being September, and that’s pretty much it.”

Strasburg has a 2.96 ERA with 181 strikeouts in 170 innings this season. The Nationals are five games back in the NL Wild Card race. The team has 10 games remaining after losing 5-2 to the Atlanta Braves on Wednesday night.

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