WASHINGTON -- Nationals manager Manny Acta has decided to give third baseman Ryan Zimmerman the day off on Monday. It will mark the second time this season Zimmerman will sit out a game.

It has nothing to do with the fact Zimmerman has a sore left shoulder. The two had decided before the season started that Zimmerman would have days off instead of trying to play all 162 games.

"I'm not concerned about the shoulder," Acta said. "He has been checked. It's just a little soreness. I don't think anybody out there on the field feels 100 percent. I don't think I am or you are 100 percent. We all have some nagging pain here and there. I don't think we'll put our franchise player out there if it were anything serious."

Zimmerman has been playing a week with a sore left shoulder. He hurt the shoulder on Sunday against the Orioles. The news first was revealed on Saturday by catcher Paul Lo Duca, who made a guest appearance on the Mid-Atlantic Sports Network. The team was not upset that Zimmerman's injury was revealed.

In the eighth inning last Sunday, Zimmerman doubled against reliever Chad Bradford and slid headfirst into second, and that's when he felt some pain in the shoulder. Zimmerman was examined and told he still can play.

On Sunday, Zimmerman said he is not bothered by the shoulder.

"If I was bothered by it, I wouldn't play," Zimmerman. "It's sore, but [if it was worse], I wouldn't play."