(AP) -- Cardinals second baseman Skip Schumaker has left Game 4 of the NL division series after grabbing his hamstring during an at-bat in the fifth inning.

The Cardinals say Schumaker had a left hamstring cramp.

It wasn't immediately clear if he would be available if the Cardinals force a Game 5 on Friday in Philadelphia.

Schumaker met with a trainer before resuming his at-bat, and eventually flied out.

A squirrel also raced across home plate during his plate appearance.

 Ryan Theriot replaced Schumaker in the top of the sixth Wednesday.

Schumaker went 2 for 3 and scored in the first. He is 5 for 8 (.625) for the series.

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