Carlos Alcaraz let loose his frustrations with a violent racquet smash in a 4-6, 7-6 (7/5), 6-4 defeat on Friday at the ATP and WTA Cincinnati Open that he called the "worst match" of his career.
The reigning Roland Garros and Wimbledon champion could not match the wily skills of 37-year-old French opponent Gael Monfils, two decades in the game and a threat to any young gun.
"It was the worst match that I ever played in my career," Alcaraz said. "I couldn't play.
"I don't know what happened. Honestly, I couldn't, I couldn't control myself. I couldn't be better. It was impossible to win, and that's all."
The Spaniard added: "I came here thinking I'm going to feel good. I'm going to put in a good tennis, because I know how to play on this court."
Alcaraz said he had never before broken a racquet in anger but this match was the exception.
The ATP No 3 and 2023 Cincinnati runner-up heads to the US Open starting a week from Monday without a hardcourt win and only one second-round summer cement match in his legs.
"It's really difficult to find some good stuffs from this match – I want to forget it and try to move on to New York," he said.
"I'll try to practice well, to get used to those courts. And I will forget this match."
Monfils then started a third-round catch-up match only hours after his victory, but ran out of puff as Holger Rune scraped out a 3-6, 6-3, 6-4 comeback victory.
While frustrated second seed Alcaraz was fuming at his form and occasionally screaming at his team, world No 1 Jannik Sinner celebrated a quiet 23rd birthday, with fate handing him a present in the form of a walkover.
The Italian advanced effortlessly into the quarters when Australian opponent Jordan Thompson withdrew before their match with a rib injury.
Sinner next gets a rematch of last week's quarterfinal in Canada, which he lost to Andrey Rublev. The Russian finished a rain-delayed match over Brandon Nakashima 7-6 (7/5), 6-1.
Third seed Alexander Zverev advanced into the last eight over Spain's Pablo Carreno Busta 7-5, 7-6 (8/6).
No 5 Hubert Hurkacz continued his quick return from July knee surgery with a 6-3,3-6, 6-1 defeat of Italy's Flavio Cobolli.
The poor run of form for seventh seed Casper Ruud continued as the Norwegian went down 6-3, 6-1 to Felix Auger-Aliassime in 68 minutes, with the Canadian sending down 14 aces.
NO1 SWAITEK CRUISES
Women's top seed Iga Swiatek defeated Marta Kostyuk for the second time this season, powering into the quarterfinals 6-2, 6-2.
The Pole backed up her win over the Ukrainian at Indian Wells last March and now stands 3-0 in the rivalry without the loss of a set.
Top-ranked Swiatek was able to finish off victory efficiently after struggling through three sets in the previous round to defeat Varvara Gracheva.
Swiatek secured the opening set in 31 minutes and was untroubled as she rolled through the second.
"I'm happy that I kept my intensity, in the first match, it got a little bit down," Swiatek said. "But I was ready in every game.
"I'm happy I was solid. I was disciplined with all the things that I wanted to take care of."
Three-time semifinalist and third seed Aryna Sabalenka beat Monfils's wife, Elina Svitolina, 7-5, 6-2 for her fourth quarterfinal here.
Sixth seed Jessica Pegula won a delayed second-round match over 2023 runner-up Karolina Muchova 5-7, 6-4, 6-2.
Pegula's second win of the day was a 6-2, 6-3 triumph over US compatriot Taylor Townsend to reach a quarterfinal against former US Open finalist Leylah Fernandez.
Mother-of-two Caroline Wozniacki lost to Anastasia Pavlyuchenkova 7-5, 6-4.
Olympic champion Zheng Qinwen beat Poland's Magdalena Frech 6-1, 7-5, but then lost a third-round match to Pavlyuchenkova 7-5, 6-1.
Teen Mirra Andreeva beat Italy's Wimbledon finalist Jasmine Paolini 3-6, 6-3, 6-2.