Novak Djokovic defeated top seed Alexander Zverev 4-6, 6-4, 6-4 to reach the China Open semifinals, maintaining his unbeaten run in the tournament.
The match was marked by an argument between Djokovic and the umpire regarding a mid-point challenge rule after advertising signage malfunctioned during a rally.
Djokovic secured the decisive break of serve at 5-4 in the third set to complete his comeback victory after two hours and 35 minutes of play.