Ivo Karlovic broke the record for the most career aces after firing down 26 in his second-round match with Pablo Cuevas at the China Open yesterday.

The 6ft 11in Karlovic moved on to 10,247 aces with his barrage, the most on the ATP Tour since records began in 1991 and 10 clear of the previous mark set by his fellow Croatian Goran Ivanisevic.

Ivanisevic, it should be noted, turned professional in 1988, three years before the records began.

Karlovic's latest fireworks were not enough for him to avoid defeat, however, as Uruguay's Cuevas claimed a 7-6 (7/5) 7-6 (9/7) triumph to progress to the quarter-finals in Beijing.

Despite not being able to mark the achievement with a win, the 36-year-old Karlovic was still thrilled with what he had done.

He said: "It's a great feeling. For the past year I knew it was possible and I was hoping that it would be this year. It's great that it happened here.

"My serve is my biggest weapon and I always take pride in it. To be able to do this is a great feeling and a great accomplishment.

"I'm not done yet. There are many years in front of me and hopefully that number will go up and up."

While Karlovic bade farewell to the tournament, top seed Novak Djokovic powered on with a 6-2 6-1 victory over Ze Zhang.

It took the world No.1 less than an hour to seal the victory, taking advantage of four of the five break points he fashioned while not conceding any to his Chinese opponent.

The Serbian, who is searching for his eight title of the year and 56th of his career, will next face American John Isner for a place in the semi-finals. Isner was a 4-6 7-6 (7/5) 6-4 winner against Australian John Millman.

Next up for Karlovic's conqueror Cuevas is Italian Fabio Fognini, who upset seventh seed David Goffin 6-2 2-6 6-2.

In the women's competition, fifth seed Garbine Muguruza fought back from a dismal first set to win her third-round match against Mirjana Lucic-Baroni and secure a place in the BNP Paribas WTA Finals in Singapore.

The Spaniard won 1-6 6-2 6-1 and becomes the third player, after Maria Sharapova and Simona Halep, to qualify for the end-of-season tournament.

Wimbledon runner-up Muguruza said: "I'm very excited to have qualified for the WTA Finals in Singapore.

"This has been an exciting year for me. I have worked very hard this last month and I am really happy how it has paid off."

Sixth seed Ana Ivanovic was another third-round winner, seeing off Svetlana Kuznetsova 7-5 4-6 6-2, but two other seeds failed to reach the quarter-finals.

Third seed and US Open champion Flavia Pennetta suffered a 3-6 6-4 6-3 defeat to Russia's Anastasia Pavlyuchenkova while fellow Italian Roberta Vinci, seeded 15th, was beaten 6-1 3-6 6-2 by American Bethanie Mattek-Sands.