The Dodgers sent reliever Tom Koehler for an MRI examination on his right shoulder Friday.
Koehler pitched to four batters Friday, retiring one. After he walked his second batter of the inning, Koehler was removed from the game, accompanied by athletic trainer Nate Lucero.
Koehler, 31, was on the disabled list for one month last season because of bursitis in his right shoulder.
He declined to speak with reporters after he left the game.
The Dodgers passed on proven and costly relievers this winter, signing Koehler for $2 million in the hope of turning him from a struggling starter into a successful reliever.
Koehler split last season between the Miami Marlins and Toronto Blue Jays, posting a 7.42 earned-run average in 13 starts and a 3.00 ERA in 14 relief appearances.