Maxwell has been dealing with pain in the ankle all season, but left Wednesday's game after four innings with intense pain in the ankle.
"It's been bothering him off and on almost all year," manager Brad Mills said. "It got to the point that it was too bad. We had to get an MRI and go from there."
Mills said no one with the Astros knows just how to proceed with the injury, so they'll talk with Maxwell and evaluate it on a day-to-day basis. Maxwell didn't start Friday, but Mills said he was available as a pinch-hitter or defensive replacement.
Mills envisions playing Maxwell for a couple days and then sitting him to see how the ankle reacts. Mills also said the injury might linger through the rest of the season, and doctors will try to manipulate the bone chip if they can.
Maxwell is batting .233/.321/.475 with eight homers and 24 RBIs on the season. He had started in 13 of the last 15 games.