Gonzalez put down a bunt as a pinch-hitter and reached first base on an errant throw from Cardinals first baseman Matt Adams. Gonzalez stepped awkwardly on the base as the throw arrived, but was able to scramble to second before bending over in pain.
"When it first happened, I thought it was an ankle," Astros manager Brad Mills said. "It was a heel bruise. Sometimes, those can be a pain. At the time, it was extremely tender. I think he did it when he hit the bag. There was a little collision there while he was coming down on the bag, and that's when it happened."
Mills and head athletic trainer Nate Lucero raced to Gonzalez's aid and removed him from the game.
Gonzalez, a Rule 5 pickup last year, is hitting .261 in 69 at-bats this year.