CHICAGO -- Second baseman Neil Walker left Saturday's game against the Cubs in the fifth inning with discomfort on his right side.
Manager Clint Hurdle believed Walker may have injured himself in his second at-bat of the day, a third-inning strikeout.
He was replaced at second base and in the batting order by Brandon Inge, who went 0-for-2 with a strikeout. Walker was 0-for-2 with a flyout and a strikeout before departing.
Walker was scheduled to be evaluated further Saturday afternoon. He entered the game hitting .246 with six home runs and 26 RBIs.
He went 1-for-4 with an RBI triple in Friday's series-opening 6-2 win against the Cubs.