Defending champion Novak Djokovic beat sixth-seeded Alexander Zverev 6-7 (6), 6-2, 6-4, 7-6 (6) to reach the Australian Open semifinals for the ninth time.
The top-ranked Djokovic has never lost at Melbourne Park after making it to the last four.
He shattered his racket in the third set by smashing it into the court when he lost a game. But that only seemed to spur a resurgence as he won the next five games to take the set.
Djokovic also had to come back from an early break in the fourth and he saved a set point before forcing a tiebreaker. He closed it out on his second match point with his 23rd ace.
He will next play Aslan Karatsev after the No. 114-ranked Russian qualifier beat Grigor Dimitrov to become the first man in the professional era to reach the semifinals at his first Grand Slam tournament.
