Stephen Strasburg has thrown his last pitch in 2012. (Getty Images)

The Stephen Strasburg shutdown was previously believed to be after one more start, but plans seem to have changed. Nationals manager Davey Johnson announced Saturday morning that Strasburg is done for the season, effective immediately.

"I just told Stephen that his year is over," Johnson said. "He's had a great year. I know what he's growing through. The media hype on this thing has been unbelievable. I feel it's as hard for him as it would be anybody to get mentally, totally committed in the ballgame. And he's reached his innings limit. So we can get past this and talk about other things for a change."

Strasburg, 24, ends the season 15-6 with a 3.16 ERA, 1.15 WHIP and 197 strikeouts in 159 1/3 innings pitched.

Johnson said Strasburg was emotional about the decision. 

The Stephen Strasburg Shutdown

"He's one heck of a pitcher, and he's a heck of a competitor," Johnson said. "I know he's been struggling with it for weeks. I know he doesn't sleep good thinking about it."

Strasburg's innings limit at the beginning of the season was believed to be 160. Later in the summer, Nationals GM Mike Rizzo said Strasburg could exceed that, just not reach 180. After a bad start Friday night -- three innings, six hits, five earned runs, three walks and two strikeouts -- plans changed. Johnson told reporters the mounting attention on Strasburg's impending shutdown was part of the equation.

"My job is to do what's best for the player, and this is what's best," Johnson said. "If you're not there 100 percent mentally -- he's a gifted athlete, his velocity can still be there -- but I don't see the crispness. I don't see the ball jumping out of his hand. I'm a firm believer that this game's 90 to 95 percent mental, and he's only human. I don't know how anybody can be totally mentally concentrating on the job at hand with the media hype to this thing and I think we'd be risking more by sending him out."

The Nationals have been put in a tenuous position. At 85-53, they sport the best record in the majors and Strasburg is among the most dominant pitchers in the league. He is also, of course, in his first full season since recovering from Tommy John surgery. So Johnson and Rizzo have been forced to balance success in 2012 with the future of the franchise's ace. Their decision now is to protect the future of Strasburg and move forward with a still-solid rotation of Gio Gonzalez, Jordan Zimmermann, Edwin Jackson, Ross Detwiler and either Chien-Ming Wang or John Lannan.

Strasburg, the No. 1 overall pick in the 2009 draft, is now 21-10 with a 2.94 ERA, 1.09 WHIP and 313 strikeouts in 251 1/3 innings pitched. He's made 45 career starts.

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