Alexander Zverev engaged in an explosive argument with the chair umpire and a French Open tournament director during a dramatic five-set defeat to Stefanos Tsitsipas in their semi-final at Roland Garros.
Tsitsipas delivered a historic breakthrough performance, becoming the first Greek player to make a grand slam final as he repelled a stirring Zverev fightback over five titanic sets.
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After three previous semi-final disappointments, it felt like Tsitsipas's moment had truly arrived on Friday at Roland Garros as the 22-year-old outstayed one of his rivals to be the next great men's tennis champion 6-3 6-3 4-6 4-6 6-3.
Zverev did tremendously well to take the match into a fifth set after appearing to unravel in a fiery third, where a disputed call saw him lash out in anger.
The German's ball was initially called out before being overruled, but rather than replaying the point, the umpire awarded it to the Greek player.
The umpire's ruling was that the call didn't determine the eventual outcome of the point, with Zverev venting his anger in a lengthy on-court rant.
“That’s bulls***. A bulls*** decision. How is that possible?” he asked.
Despite prolonged discussions with the chair umpire and tournament director at court-side, Zverev was stunned to see that the call eventually stood.
Remarkably, the German brushed aside the drama to take the third and fourth sets in a thrilling turnaround, but Tsitsipas wrestled back the momentum to book his place in the final.
"It was very difficult, very emotional," a teary Tsitsipas said in his on-court interview.
"I went through a lot of phases of emotional breakdowns - but this win means a lot, the most important one of my career so far.
"All I can think of is my roots, where I came from, a really small place outside Athens. My dream was to play in a big stadium at the French Open one day, but I never thought I could.
"A lot of people today were raising flags, cheering me on in Greece. It was very important for me to do my job well enough."
Tsitsipas holds off Zverev comeback
Yet for an agonising period, it seemed he might succumb to a fourth successive grand slam semi-final defeat as Zverev showed real backbone to claw back from two sets down.
When he earned three break points in the Greek's first service game of the decider, it felt as if Zverev might reprise his victorious comeback from two sets down in last year's US Open semi-final against Pablo Carreno Busta.
"It was nerve wracking, so intense, the most important game of the fifth set. But I came back, stayed alive, had the crowd with me giving me energy," Tsitsipas said.
"I still felt like there was hope."
The German had also come from two down to win in the first round against compatriot Oscar Otte but Tsitsipas fought off the break points to hold, before Zverev served a double en route to being broken for 3-1.
Then Tsitsipas, who had seemed to be unravelling when grumbling to himself at the end of the fourth, kept his nerve even after Zverev saved four match points on his serve at 2-5.
The Greek fired down an ace to clinch victory on his fifth match point after three hours 37 minutes.
It set up a final against Novak Djokovic, who exacted revenge on Rafael Nadal for defeat in last year's decider with a 3-6 6-3 7-6 6-2 victory.
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