Stephen Strasburg's season is over, Nationals manager Davey Johnson announced Saturday. While the decision to limit Strasburg's innings this season was made to reduce the physical stress on his surgically-repaired arm, Johnson revealed that the timing to shut Strasburg down immediately was made after the young ace appeared to struggle mentally in his start Friday.

"If you're not there 100 percent mentally -- I mean, he's a gifted athlete. His velocity could still be there," Johnson said, according to the Washington Post. "I don't see the crispness. I don't see the ball jumping out of his hand. It's more, I'm a firm believer this game is 90-95 percent mental. He's only human. I don't know how anybody can be totally concentrating on the job at hand and media hype to this thing. I think we would be risking more sending him back out."

Strasburg allowed two home runs in just three innings on Friday, giving up five hits with two walks. He finishes the season with a 3.16 ERA and 197 strikeouts in 159 ⅓ innings.

"I know he's been struggling with it for weeks," Johnson said. "I know he doesn't sleep good thinking about it. Shoot, I've heard so much advice from every ex-pitcher, every guru on the matter."

The Nationals lead the Atlanta Braves by 6 ½ games in the National League East.

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