Hayward rolled his ankle after landing from an alley-oop attempt with 6:45 remaining in the first quarter and immediately collapsed on the floor. He was on the floor for several minutes before being taken off via stretcher. His leg was placed in an air cast.

MORE: Live updates from Celtics vs. Cavs

He was replaced by Marcus Smart.

Hayward signed with Boston as a free agent this past offseason after playing seven seasons with the Jazz.