Nick Kyrgios reveals fight almost broke out after doubles upset, as Croatian pair slam Aussie crowd

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MELBOURNE, Australia -- Controversial Australian tennis star Nick Kyrgios has revealed a fight almost broke out on Day 5 of the Australian Open after he and doubles teammate Thanasi Kokkinakis sent the No. 1 ranked pairing of Nikola Mektic and Mate Pavic packing.

Kyrgios and Kokkinakis caused one of the boilovers of the tournament in knocking out the highly fancied all-Croatian team 7-6(8), 6-3 to advance to the third round of the men's doubles, their best result together at a major.

The Australian duo enjoyed wild support throughout the match on Kia Arena but at times it seemed to cross the line with the crowd frequently cheering each fault or missed shot by the top ranked team. At various stages Mektic and Pavic approached the chair umpire but little was done to calm the crowd.

Kyrgios revealed Saturday that a scuffle almost broke out shortly after the players had returned to the locker room.

"Just letting you know after yesterday's chop fest in doubles my opponents coach and trainer proceeded to threaten to fight in the players gym," Kyrgios tweeted. "Tennis is a soft soft sport @TKokkinakis all because I moved and hit them with a tennis ball."

Kokkinakis replied: "That was crazy!! Mans thought it was @ufc."

The world No. 1s, who won gold at the Tokyo Olympics last year, slammed the Australian Open crowd following the loss.

"Obviously they cheer for [the] Aussies [but] it wouldn't hurt them to show some respect to all opponents, to other players," said Pavic. "We saw yesterday also with [Daniil] Medvedev how it was. That's how they are here."

Mektic was a little more measured and opted to credit Kyrgios and Kokkinakis for the performance.

"It all went very fast," he said. "The guys played really well. They're a nasty team to beat here and that's it."

Kyrgios and Kokkinakis combined for 17 aces in the match and won a staggering 88% of first serve points.

Having knocked the top team out, they would not face another top 10 pairing until potentially the semifinals. Up next they will play the winner of German pairing Dominik Koepfer and Jan-Lennard Struff or 15th seeds Ariel Behar and Gonzalo Escobar for a place in the quarterfinals.