THEY were meant to be the saviours of a generation for Australian tennis.
But Nick Kyrgios has lifted the lid on his deteriorating friendship with fellow wild child Bernard Tomic, saying the out-of-sorts tennis prodigy has "lost his way".
It's an extraordinary development in the relationship of Australia's two biggest tennis names, and comes as Kyrgios prepares to lead Australia into a Davis Cup semi-final showdown with Belgium in Brussels (starting 10pm Friday AEST).
The pair carried the hopes of Australia when they burst on to the scene in recent years, combining at Davis Cup level, rising up the ranks on the ATP tour and generally bonding over mutual interests.
Along the way, each courted controversy.
Tomic has had occasional run-ins with the law, for driving offences and wild late-night parties.
Kyrgios infamously baited rival player Stanislas Wawrinka with a below-the-belt sledge about the Swiss star's girlfriend.
Racquets have been smashed. Matches have been tanked. Umpires and officials disrespected.
As a result, the pair has been lumped under the same banner.
When one does wrong, both find themselves copping backlash.
It was never more notable than when Australia's Olympic team Chef de Mission Kitty Chiller called out the duo ahead of the Rio Olympics.
Ultimately, both pulled out of the Games after engaging in a public slanging match with Chiller.
However, Kyrgios says the comparison is unfair: these days, he's nothing like Tomic.
"You'd also be wrong if you tried to lump me in the same category as Bernard Tomic, as Kitty Chiller and tons of others have over time," Kyrgios wrote in an article for Players Voice.
"Bernie has lost his way.
"We were pretty good mates when I was younger. I obviously didn't know the tennis tour too well back then and we were guys of similar age, representing the same country, on the road at many of the same tournaments.
"But a lot has changed since then. He needs to figure out what he wants to do. I can't relate to anything he says anymore. He says one thing and he does the other. And he contradicts himself all the time."
Tomic has created headlines for lacking motivation and struggling with the spotlight of being a professional tennis player.
Kyrgios, too, has similar concerns and accepts he's "not the professional tennis needs me to be".
But he looks at Tomic and sees a walking, talking contradiction.
"He says tennis doesn't make him happy, that he doesn't really like the game, yet he says the only thing that will really make him happy is winning a grand slam," Kyrgios added.
"It doesn't make sense at all.
"I can honestly say winning a grand slam would not make me the happiest person on earth."
After Wimbledon, Tomic declared he was "a little bored" during a listless first-round defeat to Mischa Zverev - then boasted about the wealth his tennis career has brought him.
For Kyrgios, money is not a key motivation.
"As I wrote previously, I just love being a normal guy and having enough money to live a normal life. I don't need the excess money at all. We're a lot different."
Despite that, Kyrgios admits he has much to work on to reach the level he expects of himself and he knows is expected of him.
At his best, Kyrgios says he feels "unbeatable", such as when he knocked off Novak Djokovic twice in a fortnight this year.
But he can just as easily fall off track and "tank" against lesser opponents.
It's a conundrum he admits his coaching staff must find infuriating, declaring coach Sebastien Grosjean may deserve to "work with someone more dedicated than me".
The real reason why Kyrgios believes he can't embrace the game of tennis?
Because it's distracted him from his personal life and taken him away from key moments in his life, such as being there for his beloved grandmother, Julianah Foster, when she passed away two years ago.
"I didn't get to spend the time with her I wanted to and tennis was the reason for that. It kept me away from her," Kyrgios wrote.
"It's something that still gnaws away at me.
"If I'm honest, I'd say I haven't committed to tennis the way the game needs me to since she died."
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