Novak Djokovic was left baffled by an overrule from the umpire that then got overruled itself during his fourth-round match against Lorenzo Musetti at the French Open.
A huge serve down the T from the world number one was initially called out by the line judge at the back of the court, which the umpire immediately overruled.
But upon closer inspection, the umpire then overruled himself while standing at the net as Djokovic walked over to debate the decision.
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The number one seed, clearly unhappy with the call - and subsequent double-overrule - made his feelings known to the umpire.
"That's half of the mark! Half of the mark is on the line!" Djokovic protested, laughing in disbelief.
Half of the mark is on the court and half of the mark is on the line!
"A further inspection, and he's going to have to correct his overrule," explained Eurosport commentator Chris Bradnam.
"Well he reversed his call, and then he was having to argue the case!
As Eurosport's Jo Durie, a semi-finalist at Roland Garros in 1983, noted, "As you say, Chris, he ain't gonna get anywhere! He was arguing with himself I guess!"
Shortly afterwards, there was a very nasty moment during the first set when the Italian took a tumble on an advertising board.

'Seriously nasty!' - Awful trip from Musetti on advertising board against Djokovic

At the end of what was an engrossing and entertaining rally, Djokovic pushed his opponent right to the back of the court with a smash with Musetti left very uncomfortable.
As the 19-year-old stepped back, he ended up landing on a metal advertising board at the back of the court where a line judge would sometimes be stationed.
Musetti landed with a thud and, thankfully, the board collapsed under his weight. Even more thankfully, the Italian did not sustain a nasty injury.

Highlights: Djokovic comes through big Musetti scare to reach quarters

As Durie observed, Musetti could easily have injured his ankle badly in the incident.
"Oh, careful!" exclaimed Durie, on commentary at the time. "He didn't quite know where he was on the court.
"Goodness me! He could have easily done an ankle there. The lines person did very well to get out of the way quickly."
Bradnam added: "His foot landed flat! Square on it, thankfully. That could have been the end of the match. That is so lucky!
It's not the first time that has happened, and it won't be the last. That could have been very nasty. Seriously nasty!
Djokovic could take on 13-time champion at Roland Garros, Rafael Nadal, in the semi-finals in Paris in what would be a repeat from last year's final in the postponed autumnal edition, while Roger Federer was also in the same half of the draw before he had to withdraw ahead of his fourth-round match with Matteo Berrettini.
The three most successful players in the history of the men's game have won 17 of the last 20 Grand Slam titles between them.

'It's that good!' - Djokovic shakes head at Musetti brilliance

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Watch all the action from the 2021 French Open live on Eurosport, and the Eurosport app with 13-time champion Rafael Nadal eyeing a remarkable 14th title and 2020 Roland Garros sensation Iga Swiatek aiming to replicate her stunning triumph.
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