"As of right now, he has today and tomorrow off," Williams said. "His swing is fine. The issue he has is probably throwing overload. He throws a lot and he works at it really hard, so it may be a little overload at this point."
In Saturday's 6-2 loss to the Braves, Andrelton Simmons hit what looked like a routine ground ball to Zimmerman, whose high throw to first pulled Adam LaRoche off the bag, with the ball tipping off the first baseman's glove and then bouncing into the stands, allowing Justin Upton to score to make it a one-run game.
Zimmerman was taken out of the game in the top of the sixth inning, and it was revealed that he had a sore right shoulder, which was a problem for him most of last season. Zimmerman acknowledged that the soreness never went away this past Spring Training.
"It's just sore. It was more sore yesterday than it usually is," Zimmerman said on Sunday morning. "Yesterday, I felt worse than normal. I thought it was the right thing to tell Matt, and we'll see what you got."
It has been a tough 2 1/2 years for Zimmerman. Starting in 2012, he had cortisone shots in the shoulder before undergoing surgery after the season. During the 2013 season, Zimmerman had a tough time recovering from the surgery. He had a had a tough time throwing to first until the month of September.
During Spring Training, Zimmerman had shoulder soreness during Spring Training, but the team didn't show any concerns. For now, the Nationals have not placed Zimmerman on the disabled list.
It has become apparent that if the shoulder continues to be a problem, Zimmerman could find himself at first base on a permanent basis. He played a few games at first during Spring Training.
"I don't know if I really thought about [playing first base] yet," Zimmerman said. "Obviously, I would love to play third base. I feel like I've been a good third baseman. We have to assess what's going on and see what we do."
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the time. He also could be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.