Philadelphia 76ers rookie Markelle Fultz was helped off the court after rolling his left ankle in the team's summer league game against the Golden State Warriors.
He was ruled out for the rest of Saturday's game and went to the locker room for X-rays.
Fultz was attempting to block a drive in the third quarter by Warriors guard Jabari Brown when Fultz jumped and landed on Brown's heel.
Fultz was selected as the No. 1 overall pick by Philadelphia in this year's draft.