Andrus will undergo X-rays after feeling a pop in his left ankle during Saturday's win against the Astros, Martin Gallegos of MLB.com reports.
Andrus suffered the injury while scoring the game-winning run as the A's walked off the Astros in the ninth inning. The veteran shortstop should be considered day-to-day until the results of the X-rays are known, though he at least seems unlikely to be in the lineup for Sunday's series finale.