Daniil Medvedev left the tennis world stunned on Tuesday when he tried an underarm serve on match point in his loss to Stefanos Tsitsipas at the French Open.
Tsitsipas roared to a straight-sets victory over World No.2 Medvedev to set up a blockbuster semi-final showdown with Alexander Zverev.
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Tsitsipas had to withstand some superb counter-attacking tennis from Medvedev before racing into the last-four with a 6-3 7-6 (7-3) 7-5 victory.
The match finished in extraordinary fashion when Medvedev produced an underarm serve while facing match point at 5-6.
But Tsitsipas read it perfectly and whacked a backhand winner straight past Medvedev to clinch victory.
Tennis fans and commentators erupted over the shock tactic, with opinion heavily divided about Medvedev's wisdom.
Some praised the Russian for the ballsy move, while others were quick to condemn the serve that some believe is poor sportsmanship.
The overwhelming feeling was one of disbelief that the World No.2 would try such a tactic on match point.
Tsitsipas sets up semi-final clash with Zverev
Addressing the serve in his post-match interview, Tsitsipas described it as "a very millennial shot".
"I was playing against one of the best guys on the tour and I had to keep up with the intensity and elevate my game," he added.
"I thought I was playing good and not giving him space to do things and I think my performance was close to one of my best this week.
"I love being in Paris, it brings back good memories and I'm happy to keep going."
Tsitsipas had won just one of seven previous matches with Medvedev, but the former arrived at Roland Garros favoured to reach the final after titles in Monte Carlo and Lyon.
A single break of serve allowed Tsitsipas to clinch the opening set, but the 22-year-old - beaten by Novak Djokovic in five sets in the 2020 semi-finals - had to save two set points on serve in the second before controlling the tie-break.
Medvedev broke and led 4-2 in the third but Tsitsipas swiftly hit back, and then broke again to close out victory.
"It was a very close match, there were not many breaks, we both served pretty well. It was intense," said Tsitsipas.
Tsitsipas' victory sets up a final-four clash with Zverev, who moved a step closer to becoming the youngest man in a decade to lift a grand slam singles title as he swept past Spain's rising star Alejandro Davidovich Fokina.
Zverev had too much power and know-how for the 22-year-old Spaniard, blitzing to victory 6-4 6-1 6-1 in just one hour 36 minutes.
The 24-year-old made it clear on court afterwards that he felt the win was just a stepping stone as he hopes to become the youngest men's grand slam singles winner since Djokovic at Wimbledon 2011.
"Obviously, it's very nice to be in the semi-finals but just being here doesn't satisfy me," Zverev said.
"I know I'm playing pretty okay and I hope I can continue playing the same way, maybe even better in the semi-finals and we'll see what it holds."
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