Alexander Zverev wagged his finger at his opponent, Roman Safiullin, after he attempted a cheeky serve during their French Open second-round clash.
Zverev did end up winning the match as he secured a straight sets, 7-6 6-3 7-6, victory over Safiullin to progress through to the third round but there were several contentious moments.
At 4-2 30-40 in the third set, Safiullin decided to shock his opponent with a quick underarm serve with Zverev well behind the baseline expecting a powerful delivery.
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When he responded in fine fashion with his return and then won the point, the German wagged his finger at Safiullin after punishing his attempt at catching him out.
"Well, he's wagging his finger, Zverev!" exclaimed Chris Bradnam, on commentary for Eurosport at the time.
A little naughty! It's cheeky. But it's legal too! But it cost him [Safiullin].
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Earlier, just days after being warned for being late for the start of a match, Zverev lost his temper with the umpire following yet another time violation before the match had started.
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The sixth seed got into trouble with the match umpire before his opening-round encounter with compatriot Oscar Otte had even got underway as he strolled up late for the coin toss.
When it was pointed out to him that he was late for another coin toss, the German responded to the umpire and suggested that he should just accept fines throughout the tournament for being late to the coin tosses.
Zverev cited the stand being taken by Osaka, who made the pre-tournament decision to step away from her media duties during Roland-Garros, citing a need to protect herself from the impact the duties have on her mental health. She has since withdrawn from the tournament over the issue.
"You know how Naomi said you could fine her for every single match she is not at the press conference?" Zverev asked the umpire. "You can fine me for every single match I'm late!"
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On this occasion, both he and his opponent, Safiullin, were handed time violations for not being ready to begin the match in time in what was the opening match on Court Suzanne-Lenglen.
This time Zverev was not in a jovial mood and proceeded he make his feelings well known to the umpire.
Given that Safiullin had the balls in his hand and the onus is traditionally on the server to dictate the pace of proceedings, he clearly felt as though he was not the one holding things up.
"Within four seconds I was here at the baseline," protested Zverev. "I looked at it [the match clock] and within four seconds I was here at the baseline.
I had it last time - and this time it's bulls***. I'm sorry.
Bradnam explained: "They were both starting so it's a code violation for both players because they were not ready to start within the one minute.
"He was saying, Zverev, that he was at the baseline and ready to play. Why are you giving me a warning? I'm not serving, is what he means."
Annabel Croft, also on commentary for Eurosport at the time, added: "It's kind of quite brave to give him a code violation at that particular moment, isn't it."
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Watch all the action from the 2021 French Open live on Eurosport, eurosport.co.uk and the Eurosport app with 13-time champion Rafael Nadal eyeing a remarkable 14th title at his favourite event and 2020 Roland Garros sensation Iga Swiatek aiming to replicate her stunning triumph in Paris.
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