Updated

Washington Nationals outfielder Bryce Harper was held out of the starting lineup in Monday's series opener versus the Baltimore Orioles and will likely miss Tuesday's game as well, the team announced.

Harper initially injured his knee on May 13 against the Los Angeles Dodgers, and left the 6-2 Washington victory in the fifth inning when he viciously collided into the right field wall.

Harper aggravated his injury on Sunday versus Philadelphia after a pair of head-first slides and was replaced by Roger Bernadina as a pinch-runner in the seventh.

An MRI by team doctors showed nothing structurally wrong with the knee, while the team doesn't expect the injury to sideline the second-year outfielder for long. Washington manager Davey Johnson said Monday that Harper has bursitis in the knee.

The 20-year-old leads the Nationals in batting average (.287) and home runs (12) this season.

Harper could be slotted into the lineup as the designated hitter when the Nationals' series with the Orioles moves to Baltimore on Wednesday and Thursday.

"DHing would probably be good," Johnson said. "He wouldn't run into walls."