Djokovic beats Zverev amid controversy: 32-0 in Beijing

Novak Djokovic beat Alexander Zverev 4-6, 6-4, 6-4 in two hours and thirty-four minutes in the China Open quarterfinals, extending his record in Beijing to 32 wins in 32 matches. The match's most contentious moment came in the first set, when umpire Adel Nour granted Zverev a point replay over an LED advertising board that changed during his service motion.

The incident happened at 1-0, 30-15 for the German. Zverev served, Djokovic returned, the German missed a forehand, and only then did he turn to the umpire. Nour confirmed the board had changed and called the let. Djokovic protested at length:

"If that change bothered him, he should have stopped after the serve and pointed it out. It makes no sense."

And then:

"It has to be one of the dumbest rule changes I've ever heard in my life."

Zverev defended himself, explaining he didn't know if he was entitled to a review: "That's why I went to ask the umpire".

Zverev went on to win the set 6-4, after breaking Djokovic's serve in the opening game. The 39-year-old Serb then fought off a break point in the ninth game of the second set and closed out the match on his second match point in the tenth game of the third.

With this win Djokovic surpasses Rafael Nadal for the best start ever at a single tournament in the Open era: the Spaniard had won his first 31 matches at Roland Garros, from his 2005 debut to his loss to Robin Söderling in the 2009 round of 16. Djokovic has already won six titles in Beijing, between 2009 and 2015, and this year he returned to the tournament after an eleven-year absence. He now faces Daniil Medvedev, the No. 3 seed, in the semifinals, after Medvedev beat Francisco Cerundolo 7-6, 6-3. Zverev, the No. 1 seed and world No. 2, leaves Beijing at the quarterfinal stage.