Spectators booed as the 37-year-old Djokovic walked off toward the locker room, and he stopped, turned around and responded by giving two thumbs-up.

Zverev will face defending Australian Open champion and No. 1 seed Jannik Sinner, who beat American Ben Shelton 7-6 (2), 6-2, 6-2, in Sunday's final. Zverev is pursuing his first major tournament title.

His departure sets up a Sunday men’s final between the second-seeded Zverev and the tournament’s No. 1 seed and defending champ, Jannik Sinner, who prevailed over the American