Pirates center fielder Andrew McCutchen, the reigning NL MVP, left Sunday's game in Arizona with left side discomfort, the team announced.
McCutchen was injured in the eighth inning after a swing that resulted in a game-tying sacrifice fly. He walked slowly to the dugout and needed help going down the dugout steps, according to Mike Axisa of CBSSports.com. He also kept his hand on his side.
The 27-year-old, four-time All-Star is hitting .311 with 17 homers, 67 RBIs and 17 steals in 108 games this season for the Pirates, who entered the game 59-51, one game behind the Brewers for first place in the NL Central.
McCutchen, who was hit in the back by a pitch in the ninth inning of Saturday's game, has played at least 154 games in each of the last four seasons.
- Chris Mascaro