On Saturday, Zimmerman made another key error in the third inning of Washington's 3-1 loss to Atlanta. In that frame, Upton hit a routine ground ball to Zimmerman, who threw the ball past first baseman Adam LaRoche. It should have been the third out of the inning, and it proved costly. The next hitter, Evan Gattis, hit a two-run homer.
Zimmerman made his third error of the series Sunday, when his throw drew LaRoche into Ramiro Pena at first base, the slight collision causing the ball to fall from LaRoche's glove, allowing Pena to reach safely.
"If you look at [Zimmerman's] throwing, you are going to see a few more errors over there this year," the scout said. "He is struggling over there trying to get it right. After a while, it's going to become a mental situation. Eventually, he's going to have to come off third base."
Zimmerman had right shoulder surgery last offseason, and on a scale of 1-to-10, Zimmerman rated his shoulder a 9-plus.
"The shoulder is fine. Everything is fine. Everything feels good. Everything is great," Zimmerman said before Sunday's game. "Everyone always asks me how I throw or what I throw. Nobody throws the same and nobody hits the same. It's just how I throw. It's the way it is."
When asked about the errors the last two games, Zimmerman said, "It happens. The play during the night game was a really tough play. Yesterday, it was an error. People make errors. It's going to happen again before the year is over. Everyone is going to make errors. It's part of the game. Nobody wants it to happen. Of course, you feel bad. You play baseball long enough, that kind of stuff happens. It's part of the game. If you let it consume you, that's what gets you."
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.