Gallo injured the ankle trying to beat out an infield hit in front of home plate in the sixth inning. He stepped on first base awkwardly as he was thrown out by Indians catcher Yan Gomes.
"I was a little worried because it bothered me more than it usually does so I wanted the doctor to look at it," Gallo said. "It's just a sprain, I've played through those before."
Gallo, who started in right field, stayed in the game in the seventh inning defensively but was replaced in the eighth by Ryan Rua. It was about the same time that outfielder Scott Heineman was taken out of Triple-A Round Rock's game.
But the Rangers said that had nothing to do with Gallo. Heineman was pulled because of some soreness in his left shoulder.
Right now, Gallo is listed as day to day.
"He came out for precautionary [reasons], really," manager Jeff Banister said. "It was his last at-bat, little swinging bunt, he hit the bag a little sideways, rolled it a little bit, a little painful for him. We just felt that it was best to get him out, get him looked at and see where we are at."
Gallo was making his second Major League start in right field because Nomar Mazara is on the disabled list with a sprained right thumb. He threw out Jason Kipnis trying to go from first to third base on a single in the second and doubled off Melky Cabrera in the fourth.