Unable to make a regular, comfortable throw to first, Washington Nationals third baseman Ryan Zimmerman was out of the lineup Sunday and awaited the results of an MRI on his right shoulder.
Manager Matt Williams said the MRI showed no "structural issues" and that Zimmerman will be reevaluated after Monday's day off.
"The issue he's got is probably throwing overload," Williams said after Sunday's series finale against the Atlanta Braves. "He throws a lot, and he works at it really hard, so it may be a little overload at this point."
Zimmerman has already made two throwing errors this season, including a two-out misfire Saturday night that led to a pair of unearned runs in a 6-2 loss to the Atlanta Braves.
"Through spring and last year and things like that, it felt good sometimes, it felt bad sometimes," Zimmerman said before Sunday's series finale. "But it's never really felt like this."
Zimmerman's shoulder has been bothering him for two years. He committed 12 throwing errors in 2012 and, after off-season shoulder surgery, committed 16 last year. His throwing improved late in 2013, but the wildness prompted consideration that he might have to make a permanent move to first base.
Williams plans to use Zimmerman at first occasionally this season, but the manager doesn't yet see it as a full-time move.
"We'll do what we have to do, but I envision him playing third base," Williams said. "That's the plan. Of course, you have to look at things and adjust if need be, but as of right now, as soon as he feels good, he'll be back at third."
Zimmerman said he didn't know if he would be headed to the disabled list until he learned the results of the MRI.
"I feel like I've been a good third baseman," he said.
Cool weather bothersome
Zimmerman said the early-season cool weather hasn't helped. Curiously, he remains accurate when he's charging the ball and slinging it on the run.
"It feels OK sidearm, things like that," he said. "That's where I've always felt more comfortable. But it's just hard to explain."
Also Sunday, the Nationals placed outfielder Scott Hairston on the 15-day disabled list. Hairston strained his left oblique (rib cage) while swinging during an at-bat against the New York Mets on Thursday.
"Obviously in this game, the more and more you swing, if you have an issue going on, it's not going to get better unless you rest it," Hairston said.
Hairston said he's had oblique problems before, but this one isn't as bad. He guessed he'd be back in less than four weeks.
"I don't think it's anything severe," he said. "I was able to have an at-bat last night without taking myself out of the game."
Replacing Hairston on the roster is first baseman-outfielder Tyler Moore, who was recalled from triple-A Syracuse.
Hairston's injury and Zimmerman's shoulder problems, along with slugger Bryce Harper's early slump, led to an unusual lineup Sunday for this early in the season. With Harper (batting .143) sitting out, Kevin Frandsen was playing outfield for the first time since 2010.
"It's one of those things you have in your back pocket," Frandsen said. "Is it easy? Not all the time. It's something different from the infield. But at the same time, you just be an athlete. Go out and catch the ball."