Nick Kyrgios has come to the defence of Daniil Medvedev and condemned a fan's 'disgusting' behaviour after video of the World No.1 in a heated confrontation emerged on social media.
Kyrgios caused a massive boilover at the Canadian Open last week when he beat Medvedev to continue his sparkling form in the lead-up to the US Open.
Kyrgios took down the Russian star 6-7(1) 6-4 6-2 for his third victory over Medvedev in four career meetings and his second victory over a current World No.1.
But the loss for Medvedev took an ugly turn on Sunday when video emerged on social media of the moment he confronted a heckling fan after the match.
In the video, Medvedev can be seen leaving the arena when he is called a 'loser' by a man standing nearby.
Medvedev then turns and walks up to the man, giving him a piece of his mind as security moves in to calm things down.
After a lengthy exchange, Medvedev continues on his way.
On Sunday night, Kyrgios took to Twitter to slam the man's behaviour.
“Disgusting behaviour. This is the best we have in the sport, fans need to show some respect," he wrote.
Kyrgios' victory over Medvedev has left the Russian star in danger of losing his World No.1 ranking.
Because he won the ATP 1000 event in 2021, he will lose a mountain of points and leave the door ajar for Rafa Nadal to pounce.
Currently World No.3, Nadal can reclaim the top spot if he wins this week's Cincinnati Masters - with World No.2 Alexander Zverev still sidelined by the injury he suffered at the French Open.
Even if Nadal doesn't win in Cincinnati, he has a real shot of taking Medvedev's mantle at the US Open, with the Russian defending another swathe of rankings points after winning the grand slam last year.
Nick Kyrgios runs out of steam at Canadian Open
Kyrgios' nine-match winning streak came to a disappointing end in the quarter-finals in Montreal, worn down by fatigue, a sore back, and the implacable serving of Polish star Hubert Hurkacz.
The No.8 seed won 7-6 (7-4) 6-7 (5-7) 6-1 on Saturday, with the final set taking 27 minutes after the first two lasted 38 and 41 respectively.
Kyrgios did not call a trainer, or complain, but looked off the pace physically. He also had plenty on his mind with his parents unwell at home in Australia.
"I honestly don't care [about losing the winning streak]," said Kyrgios.
"I've been away from home, away from my mum, away from my dad.
"They're not very well at the moment. So I don't really care about 'no winning streak'.
"I got two more tournaments [Cincinnati and the US Open] left before I can go home."
Kyrgios had won 15 of his past 16 singles matches, with the only defeat coming against Novak Djokovic in the Wimbledon final.
But that is a lot of tennis for a player who has pursued a much less busy schedule in recent years.
In Washington last week he won the singles and doubles titles, playing 10 matches in all.
The loss against Hurkacz was his 15th match this month in the American hard-court swing.
"Nick was maybe a little bit injured, which might have hurt his serve," said Hurkacz.
"With both of us serving so well, that few per cent can make the difference."
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