The Thunder announced Thursday that Williams is out with a right hamstring strain and will be re-evaluated after the preseason, Brandon Rahbar of DailyThunder.com reports.
It's unclear if Williams will miss any regular-season action, but hamstring injuries can often linger. With Kenrich Williams (knee) also out, Ousmane Dieng could receive increased playing time off the bench in Oklahoma City's frontcourt early in the campaign.