Nick Kyrgios has lone ever faced Karen Khachanov from crossed a nett doubly successful their tennis careers.
But don't beryllium fooled - there's buckets of atrocious humor betwixt the brace that lone adds to what volition beryllium a quarter-final US Open blockbuster.
It stems from a Twitter feud that erupted 2 years ago, a bitter back-and-forth that began with the Aussie sticking up for his person Andy Murray.
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Late successful 2020, astatine the tallness of the COVID-19 pandemic, Kyrgios took purpose astatine tennis large Mats Wilander for labelling Murray "selfish" implicit his determination to judge a Roland-Garros wildcard.
Khachanov, astatine that clip ranked 16th successful the world, asked Kyrgios to "show immoderate respect", but the Canberra firebrand didn't instrumentality excessively kindly to the request.
"Nah I'm bully dude. Muzz (Murray) and I respect each other, and if idiosyncratic starts talking astir 1 of excavation past I'll travel astatine them," Kyrgios fired astatine Khachanov connected Twitter.
"I'm expected to respect Mats? For what? Hitting a shot implicit the net? I don't springiness my respect for that."
The Russian subordinate replied; "Bro it's your call".
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"I truly deliberation you are a bully lad and I don't person immoderate occupation with you. But erstwhile you are sitting astatine location and penning antithetic comments astir players that makes maine deliberation who has the existent problem."
Kyrgios was astatine the clip opposing the actions of Novak Djokovic and Alexander Xverev, who had attempted to tally a tourney successful the look of COVID-19.
"So you deliberation what the players did during this pandemic was smart?" Kyrgios tweeted astatine Khachanov.
"I'd emotion to person an intelligence speech with you but I'm not definite it would spell further than however hard you could deed a ball. I've simply been holding radical accountable."
The Russian rapidly fired back.
"Next clip earlier talking astir my intellect work astatine slightest a fewer books, alternatively of playing video games [the] full time long," Khachanov said.
Kyrgios again fired back.
"I've besides been feeding the hungry, helping unfastened up caller facilities for kids to get active. But mode to bash your probe you implicit pelican."
Their long-running feud adds spice to the quarter-final clash connected Arthur Ashe Stadium.
Kyrgios takes retired Medvedev with ace
Kyrgios is present the US Open favourite aft eliminating Daniil Medvedev successful 4 sets, and Rafael Nadal was bundled retired of the moving the pursuing day.
Australian tennis large Wally Masur warned Khachanov volition contiguous a superior situation for Kyrgios.
"He's playing well, but this is simply a pugnacious match," Masur told Stan Sport's Grand Slam Daily.
"These men person played connected a mates of occasions, it's 1 apiece. It's been a fewer years since they person played.
"They've played 8 sets, six of those sets were tiebreaks. Kachanov has a large serve, he's six (foot) six (inches), he's a hard antheral to interruption down.
"He won't beryllium intimidated by Nick's powerfulness oregon tribunal presence, due to the fact that helium is physically imposing himself.
"Nick, I believe, is surely playing the amended tennis of the 2 close now, and he's a amended fast-court player. But helium volition person to beryllium connected his game."
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