Ventura departed after Jose Altuve fouled off a pitch in the third inning Monday night.
Manager Ned Yost and trainer Nick Kenney went to the mound and Ventura was led off without attempting another pitch. He was replaced by Michael Mariot.
Ventura will have a MRI Tuesday.
He faced 18 batters in 2 2-3 innings, giving up five runs on seven hits and three walks.
Ventura, whose fastball routinely hits 100 mph, was 2-4 with a 3.45 ERA coming into the game.