The Nationals have surged four games clear of the NL East pack despite little contribution from Zimmerman, the franchise player who bats third and signed a $100 million contract extension in the offseason. His .655 OPS is the worst on the team, and he has only three home runs in 205 plate appearances.

“I just don’t see him tracking real well,” Manager Davey Johnson said. “I don’t know why, if it’s his approach of what he’s thinking. I know he can be streaky at times. But I sure need him to be comfortable, because he’s invaluable to this ball club.”

Zimmerman seemed ready to break out at times this weekend in Boston. He laced an RBI single to center field and nailed several liners right at fielders. But in Toronto, he has looked as uncomfortable as ever. Zimmerman has gone 1 for 9 with three strikeouts and grounding into a double play.

Zimmerman’s season was interrupted by inflammation in a right shoulder joint. He has not used the injury as an excuse, consistently saying he would not be playing if he did not believe he was capable. But the injury has prevented Zimmerman from his typical, full complement of batting practice.

“He’s hard for me to read,” Johnson said. “He’s so talented. He went through spells where he hit it at people and hit balls that went nine miles and the wind kept it in the ballpark. But I haven’t seen him hitting the ball like that. I don’t know if his shoulder has been bothering him or what, but we certainly need him.”

Watching Zimmerman in batting practice, Johnson has seen the typical Zimmerman, driving balls to all fields. But “he looks real defensive in the game,” Johnson said. Zimmerman has continued to bat third throughout his struggles, and Johnson indicated that is not about to change.

“He’s too good of a hitter to keep struggling,” Johnson said. “There’s plenty of time to pick up the slack and start carrying a heavy load.”

One more note on Zimmerman: He will host his annual charity event at Nationals Park on Thursday to support ziMS, his foundation that fights multiple sclerosis. You can find information here, and read here why it matters so much to him.

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