Wallace has been diagnosed with a torn labrum in his left shoulder and will require surgery, Shams Charania of ESPN reports.
Although Wallace's return timetable has yet to be determined, Charania notes the guard is expected miss most of, if not all, of the rest of the season. It's been a brutal day for the Thunder, who also lost Jalen Williams (ankle) on Monday and will need Ajay Mitchell, Jared McCain and Alex Caruso each to step up for the foreseeable future.