The end of the 2018 season hasn't gone to plan for Nick Kyrgios, with the Australian suffering a first round loss at the Shanghai Masters.
Kyrgios appeared exasperated and distracted at times as American qualifier Bradley Klahn took out the match in three sets.
The Aussie looked solid in the opening set as Klahn - ranked 104 in the world - didn't look overly threatening to Kyrgios' charge.
However, during the second set, Kyrgios wasted a golden chance on serve when he was down 4-5, and Klahn pushed the match to a deciding set.
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Kyrgios began to slide, and was down 0-3 in the third set - a startling set of circumstances given he had lost five straight games from 4-4 in the second set.
As Klahn worked his way towards a win, his frustrated Australian opponent engaged in an argument with French umpire Damien Dumusois.
During the second set, Dumusois was overheard telling Kyrgios a point in the second set was "really borderline".
Dumusois' comments, which appeared to suggest a lack of effort, prompted Kyrgios to respond: "I don't care... you have no right to tell me that it's poor".
Nick Kyrgios lost his temper with chair umpire Damien Dumusois during another ignominious Shanghai Masters exit on Monday.
— Sky Sports Tennis 🎾 (@SkySportsTennis) October 8, 2018
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Later, after belting down an ace, Kyrgios sarcastically asked Dumusois: "Was that borderline?"
Klahn eventually wrapped up the match in one hour and 17 minutes, winning 4-6 6-4 6-3.
While not a clear-as-day accusation of tanking - like some others have freely done in the past - Dumusois' comments clearly didn't go down well with the 23-year-old.
As Klahn accepted the plaudits from the crowd, Kyrgios left the court using his mobile phone.
It's the third year on the bounce in Shanghai that Kyrgios has departed the tournament in controversial circumstances.
In 2017, he copped a $10,000 fine for unsportsmanlike conduct during a match against American Steve Johnson. On that day, he belted two balls out of the stadium, and walked out midway through the match.
In 2016, he copped a $16,500 fine following a straight sets to Germany's Mischa Zverev. On that day, he gave minimal effort on serve, and on one occasion, he even began walking back to his chair before a serve from Zverev.
During last month's US Open, an umpire copped a ban after he gave Kyrgios a bizarre mid-match pep talk.
Regardless, now ranked 38, Kyrgios will need to work hard to grab a seeding for next year's Australian Open in Melbourne.
Last week, Kyrgios ceded his spot as Australia's highest-ranked male player to Alex de Minaur following a defeat at the Japan Open.
De Minaur will kick off his Shanghai campaign on Tuesday against Poland's Vasek Pospisil.
He will look to join fellow Aussie Matthew Ebden, who fought after losing the opening set to defeat American Frances Tiafoe in three sets, 3-6 6-4 6-3.
The win over Tiafoe has left Ebden facing a tough second round encounter against world No.7 Dominic Thiem.
