Bryce Harper (shoulder bruise) returns to Nationals' lineup

Bryce Harper initially bruised his left shoulder trying to make a catch in Tuesday's game against Atlanta.

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ATLANTA -- Washington Nationals left fielder Bryce Harper was in the lineup Thursday night against Atlanta after X-rays on his left shoulder were negative.

Harper winced on a check swing in the sixth inning of Washington's 2-0 victory on Wednesday and soon left the game.

Harper said he was diagnosed with a bruise under his left shoulder blade. Washington manager Davey Johnson said Harper is taking medication to relieve swelling.

The 20-year star ranks among the top five in the National League in homers, batting average and assists.

Harper was originally hurt on Tuesday when he crashed into the wall trying to catch a home run hit by Braves pitcher Tim Hudson.

Nationals right fielder Jayson Werth returned to the lineup after missing two straight games with a strained right hamstring and a bruised left ankle.