Controversial Australian tennis star Nick Kyrgios defeated Russia's Daniil Medvedev in the fourth round at the US Open on Sunday. It took Kyrgios two hours and 56 minutes to prevail 7-6(11), 3-6, 6-3, 6-2.He will play another Russian, Karen Khachanov, in the quarterfinals, who beat Pablo Carreno 4-6, 6-3, 6-1, 4-6, 6-3 in three hours and 21 minutes. Kyrgios and Khachanov have a bit of unpleasant history between them, having engaged in a Twitter feud back in 2020.When former World No. 1 Mats Wilander questioned Andy Murray's decision to accept a wildcard slot at the 2020 French Open, Kyrgios and Khachanov got into an argument over Kyrgios' criticism of Wilander.The duo traded blows on the social media platform and Kyrgios referred to Khachanov as an "absolute pelican."Vansh@vanshv2kNicholas Kyrgios vs Karen Khachanov US Open 2022 QF1127159Nicholas Kyrgios vs Karen Khachanov US Open 2022 QF https://t.co/9K1PTY1TVMIn view of their upcoming quarterfinal clash, tennis fans on Twitter recalled that feud and shared their opinions on the incident. One user remarked that Kyrgios constantly demonstrates how immature he is by engaging in such behavior."Kyrigos proves time and time again what an absolute adolescent he is."RubyGirl💓✌😎☮️@ebrownberry8@vanshv2k Kyrigos proves time and time again what an absolute adolescent he is.@vanshv2k Kyrigos proves time and time again what an absolute adolescent he is.Another user jokingly stated that because of Nick Kyrgios, they would start using the term "pelician.""The way I’m about to start calling people pelicans from now on because of @NickKyrgios, lmfaoooooo," the user wrote.That’s that Thique@layla_jobThe way I’m about to start calling people pelicans from now on because of @NickKyrgios lmfaoooooo twitter.com/vanshv2k/statu…Vansh@vanshv2kNicholas Kyrgios vs Karen Khachanov US Open 2022 QF1139160Nicholas Kyrgios vs Karen Khachanov US Open 2022 QF https://t.co/9K1PTY1TVMThe way I’m about to start calling people pelicans from now on because of @NickKyrgios lmfaoooooo twitter.com/vanshv2k/statu…According to another user, Kyrgios is a "douche" and Khachanov is correct."Khachanov still not wrong. Kyrgios still a douche," the user tweeted.Al Loh@game_set_go@vanshv2k Khachanov still not wrong. Kyrgios still a douche.@vanshv2k Khachanov still not wrong. Kyrgios still a douche.Here are a few more reactions:Pαul@JustFedererFan@vanshv2k If it's a Rafa Kyrgios final, then I hope Rafa absolutely crushes his soul and tennis3@vanshv2k If it's a Rafa Kyrgios final, then I hope Rafa absolutely crushes his soul and tennisAnkit Singh@ankit_singh11@vanshv2k My heart says Karen may win for just the conversation here or standing up for fellow players against Nick's bully like tirade but head says otherwise you know 🙃3@vanshv2k My heart says Karen may win for just the conversation here or standing up for fellow players against Nick's bully like tirade but head says otherwise you know 🙃Andre R@RolembergAndre@vanshv2k It just strikes me as such a petty, non-argument that he's bring up his philanthropy as a reason for people not to criticize him. What, does he think because Tony Stark said it he can too? That only makes him look more selfish? Idk man, this guy is an enigma.541@vanshv2k It just strikes me as such a petty, non-argument that he's bring up his philanthropy as a reason for people not to criticize him. What, does he think because Tony Stark said it he can too? That only makes him look more selfish? Idk man, this guy is an enigma.Tennis Pendejo@TennisPendejo@vanshv2k I guess we're just gonna skip over the part where Wilander was eventually proven wrong.16@vanshv2k I guess we're just gonna skip over the part where Wilander was eventually proven wrong.Coxy.t1@zilzey@vanshv2k There’s always one flog that resurfaces absolutely nothing… feel sorry for you bud.@vanshv2k There’s always one flog that resurfaces absolutely nothing… 😂 feel sorry for you bud.Francky Ogne 🏳️‍🌈🇨🇩 #ototombe@FranckyOgne@vanshv2k Karen introduced himself into the convo... should have minded his own business@vanshv2k Karen introduced himself into the convo... should have minded his own businessGeno@phillyguy23777@vanshv2k @BuzzerPicks I've never heard someone called a Pelican before!!🤣🤣🤣2@vanshv2k @BuzzerPicks I've never heard someone called a Pelican before!!🤣🤣🤣Alberto FM@FanjonAlberto@vanshv2k Khachanov picked up the fight tbf 1@vanshv2k Khachanov picked up the fight tbf 😂Itsarapong intoum@ArchDragoon@vanshv2k let them have boxing gloves instead...@vanshv2k let them have boxing gloves instead...Fiona@phizzog11@vanshv2k I do love ‘you absolute pelican’.@vanshv2k I do love ‘you absolute pelican’."I think Wimbledon showed him what he's capable of" - Karen Khachanov on his opponent Nick Kyrgios2020 Men's ASB Classic - Day 2In a press-conference following his victory over Pablo Carreno Busta in the last 16, Karen Khachanov spoke about his quarterfinal opponent. Khachanov believes that Kyrgios' run to the Wimbledon final has given him a fresh outlook which has fueled his current success."I think the Wimbledon showed him if he does the things like he does now which kind of level he has, what he's capable of. Obviously everybody knows that, the way he's serving," Khachanov said. SportsLumo@SportsLumoNick Kyrgios and Karen Khachanov are scheduled to face each other on Tuesday, September 6 in the quarter-final of the 2022 US Open.#USOpen #USOpen2022 #ATP sportslumo.com/tennis/kyrgios…Nick Kyrgios and Karen Khachanov are scheduled to face each other on Tuesday, September 6 in the quarter-final of the 2022 US Open.#USOpen #USOpen2022 #ATP sportslumo.com/tennis/kyrgios…The Russian also discussed his tactics for their forthcoming quarterfinal match, emphasizing the importance of his service games."I think the thing would be the same for me, focus on serve, keep the serve. In rallies we have the same, equal chances. It will be always the question of how the point starts, with the serve and return," the Russian said. Also Check out: US Open 2022 Schedule