Thumb soreness chases Morse Monday. (Getty Images)

Nationals outfielder Michael Morse left Monday's game against the Cubs after just one plate appearance. Roger Bernadina pinch hit for him and the Nationals have said that Morse was removed due to right thumb soreness.

This issue is concerning for the Nationals because Morse has been dealing with thumb problems for a few weeks -- and with them have come struggles at the plate. Since August 17, Morse has hit .222 with zero home runs, two walks and 13 strikeouts in 49 plate appearances.

If Morse was forced to miss an extended amount of time, Bernadina would be the everyday replacement, though Tyler Moore, Mark DeRosa and Steve Lombardozzi would also be candidates to see an uptick in playing time.

Morse, 30, is hitting .288/.319/.455 with 12 homers and 47 RBI in 339 plate appearances this season.

The Nationals entered Monday with the best record in baseball.

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