The outfielder was limping after running to third on an inning-ending popup. Los Angeles manager Joe Maddon said after his team's 7-4 victory that Trout was undergoing further evaluation, including an MRI, and the Angels will know more on Tuesday.
"I saw nothing. I looked up and he was limping to the third base bag,'' Maddon said. "It was kind of innocuous, and I had no idea why. It was hurting him pretty good.''
The three-time MVP entered the day sixth in the American League with a .333 batting average but was 1-for-17 in his past six games. He snapped a five-game hitless streak Sunday at Boston, which was one game shy of the longest of his career.
Trout has missed at least 22 games in each of the past three 162-game seasons. He missed no more than five in each of his first four full seasons in the majors.