Australian Nick Kyrgios crashed out of the Shanghai Masters and appeared to give up during a 6-3 6-1 defeat to qualifier Mischa Zverev.
Kyrgios, 21, had said he was "bored" after a first-round victory over Sam Querrey, which followed a run to the Japan Open title last week.
The Australian's antics got us thinking: is he alone in struggling to love his sport?
Nick Kyrgios - Tennis
Not good enough today on many levels, I'm better than that. I can go on about excuses but there are none. Sorry #StillAWorkInProgress ????
-- Nicholas Kyrgios (@NickKyrgios) October 12, 2016
Being tipped as a future Grand Slam champion doesn't seem to appeal much to Kyrgios. The 21-year-old has professed his preference for basketball over tennis, and it shows.
From shouting at umpires to cursing his own poor form and frustration, the Australian rarely seems happy on the court.
His latest incident in Shanghai, lofting a serve up for Zverev to smash back, has left the sport red-faced again. Does Kyrgios have the desire to fulfil his potential? It doesn't look like it.
Andre Agassi - Tennis
The American tennis star of the Nineties revealed plenty with the release of his autobiography, Open. In it, the four-time Australian Open champion acknowledged taking crystal meth, but also revealed his feelings for his sport.
"I play tennis for a living even though I hate tennis, hate it with a dark and secret passion," he wrote.
Still, he managed eight grand slams in an era dominated by fellow American Pete Sampras. Imagine how many he could have won if he was enjoying himself?
Benoit Assou-Ekotto - Football
As a Premier League player in the 21st century, Benoit Assou-Ekotto could have maximised his earnings and sponsorship deals, but instead he prefers to buy £23 football boots from eBay.
Assou-Ekotto's just not all that interested in the big-money benefits of being a modern footballer, telling The Guardian: "The world of football is not good."
The former Tottenham player went on to say: "It's a good job and I don't say that I hate football but it's not my passion." Football's just not that big a deal for Benoit.
Ronnie O'Sullivan - Snooker
For a five-time world champion, it seems a little odd to suggest Ronnie O'Sullivan hates snooker. And it would be wrong to make that statement without context.
The Rocket has endured what appears to be a love-hate relationship with the baize throughout his career, swearing, hitting the table, conceding matches early on and taking huge amounts of time out from the season.
But when he's on good terms with the sport, there's no-one better or more entertaining. He has the record for the most 147s in tournament play, as well as the quickest maximum in history (five minutes 20 seconds).
Paddy Barnes - Boxing
Back in 2010, Northern Irish light-flyweight boxer Paddy Barnes had just begun his Commonwealth Games campaign with a win against Scotland's Iain Butcher. He would go on to win the Commonwealth gold, but his brutal honesty after the fight came as a shock to some.
"I don't really watch boxing," he said. "I find it boring - it's all holding and grappling."
The Olympic bronze medallist went on to say he didn't mind watching Manny Pacquiao or Marco Antonio Barrera, but of his next opponent he said: "I'm fighting the Australian next and I don't know a thing about him."
So not exactly a student of the game, then.