He said he first felt the tightness chasing a ball to the foul line in the bottom of the second inning. He led off the top of the fourth inning with a walk and ran slowly as he scored from first base on Yasmani Grandal's double to right-center.
When he reached the dugout, Kemp spoke to manager Dave Roberts, who then pointed at the bench. When the inning was over, Kemp was replaced in left field by Joc Pederson.
Kemp has been the Dodgers' most productive right-handed hitter, with four homers and 12 RBIs in 22 games.
"This has never happened, so I don't know," Kemp said. "Just a little sore right now. I got treatment and tomorrow I'll see how I feel and go from there."
Ken Gurnick has covered the Dodgers for MLB.com since 2001.