Young will rehab the ankle through the weekend, sources said. He has been ruled out for Thursday night's game vs. the Miami Heat.
After he needed help to leave the court in Atlanta's loss to the Heat on Tuesday night, X-rays on his ankle were negative, and team doctors decided on Wednesday that an MRI was unnecessary.
Young has had a remarkable start to the season, leading the Hawks to a 3-0 start on 34 points per game.
Young went down on a drive to the basket early in the second quarter on Wednesday. He appeared to twist his ankle upon landing on the foot of Heat forward Justise Winslow. He struggled to put weight on his foot as he was helped to the locker room.
Young, 21, was second in the Rookie of the Year voting to Dallas' Luka Doncic last season.