Watch: Nick Kyrgios swears at umpire after crashing out of Western and Southern Open

Scroll down for all the video clips from his remarkable outbursts

The mercurial Australian unleashed a profanity-laced tirade at the chair umpire, Fergus Murphy.

Kyrgios won the opening set despite foot and ankle issues, but after a rant he threw his towel over a camera, forcing the broadcasters to switch to an overhead view.

After Khachanov won the second set, Kyrgios shouted: "The worst f***ing ref ever, the worst ref in the game.

"The worst, hands down. Every time I play he's doing some stupid sh*t, every time."

He then left the court with two rackets, despite being instructed not to do so, and proceeded to destroy them both in a corridor before returning to complete the match.

At the end of the match Kyrgios unleashed on Murphy again, saying: "You're a f***ing tool bro."

But he did at least hand one of his broken rackets to a young fan.

Khachanov now moves on to the third round and will take on Frenchman Lucas Pouille, who beat Canadian Denis Shapovalov 6-4 6-4.

Kyrgios is likely to face disciplinary action for his outbursts.

Nick Kyrgios controversies

Wawrinka sledge, March 2015

Fans' favourite Stan Wawrinka was in Kyrgios' firing line at the 2015 Rogers Cup with a crude remark about his then girlfriend, fellow player Donna Vekic.

The ATP fined Kyrgios 10,000 US dollars as well as handing down a 28-day tour suspended sentence.

Wawrinka tweeted: "So disappointing to see a fellow athlete and colleague be so disrespectful in a way I could never even imagine."

Wimbledon meltdown, June 2015

After a number of controversial calls went against him, Kyrgios went into meltdown mode during his fourth-round match against Richard Gasquet at Wimbledon.

He got a code violation for swearing, argued with the umpire over whether he was taking too long to change his socks and hurled his racket into the air.

As a chorus of boos rang around the court, Kyrgios told his entourage in the coaching box to leave - bowing out of the tournament in four sets.

Shanghai strop, October 2016

Kyrgios was banned from tennis for eight weeks after appearing to give up during a straight-sets defeat to qualifier Mischa Zverev at the Shanghai Masters.

On several occasions, Kyrgios patted down tame serves or wandered off court while the rally was still going on.

He later defended his behaviour by saying he did not owe the spectators anything and that fans could "just leave" if they did not like his attitude.

The ATP fined the Australian 16,500 US dollars for failing to give a full effort, unsportsmanlike conduct and verbal abuse of a spectator.

Kyrgios was then fined an additional 25,000 US dollars and suspended for the rest of the season, a penalty that was reduced on the condition he sought psychological help.

More Shanghai drama, October 2017

The following year, Kyrgios was fined again after retiring during a first-round match against Steve Johnson without any apparent health issues.

Kyrgios had responded to receiving a point penalty from the umpire during the tie-break by saying he would retire if he lost the game.

Queen's bottle incident, June 2018

Another fine came Kyrgios' way last summer after he was caught on TV mimicking a sex act with a water bottle during a change of ends at the Fever-Tree Championships. The BBC was forced to apologise to viewers.

Underarm or underhand?, February 2019

Kyrgios did not break the rules but left Rafael Nadal distinctly unimpressed after attempting an underarm serve during a clash with the Spaniard at the ATP Tour event in Acapulco.

The tactic is considered unsportsmanlike by some and Nadal accused Kyrgios of being disrespectful.

The Australian has continued to use the serve in matches, with varying degrees of success, and other players have followed his example.

Raging in Rome, May 2019

One of Kyrgios' most spectacular meltdowns came at the Italian Open in May during a second-round clash with Casper Ruud.

The Australian reacted furiously to being docked a game for swearing at a line judge early in the third set.

He hurled a chair across the court before packing his bag and walking off before he could be officially defaulted.

He forfeited his prize money and was fined but did not face a ban.

Queen's outbursts, June 2019

Kyrgios picked up more than £13,000 in fines in one day at Queen's Club, with several flash points across two matches.

Umpire Murphy was again in the firing line, with the line-calling the subject of Kyrgios' ire, and the Australian bizarrely mocked the Irish official's hat.