Young's sprain was diagnosed as a Grade 2 severity and he's expected to return once the swelling and discomfort subside, a source told ESPN's Adrian Wojnarowski.
The 22-year-old left Atlanta's overtime loss Wednesday to the New York Knicks in the third quarter after falling awkwardly following a shot attempt. He was helped to the locker room and didn't return to the game.
Young is averaging 25.3 points, 9.6 assists, and 3.9 rebounds per contest in his third season.
Wednesday's defeat flipped the Hawks and Knicks between fourth and fifth in the Eastern Conference standings.