Is Kyrgios running out of time to mature?

Nick Kyrgios returns to the US Open with questions swirling over whether the mercurial Australian will ever mature in time to fulfil his vast potential.

Two weeks after receiving a record six-figure fine for his latest on-court meltdown, Nick Kyrgios returns to the US Open with questions swirling over whether the mercurial Australian will ever mature in time to fulfil his vast potential.

Kyrgios, the 28th seed who will play American Steve Johnson in the first round on Tuesday, arrives in New York on the back of a second round loss at the Cincinnati Masters where he again made headlines for all the wrong reasons.

He was fined $113,000 there after verbally abusing chair umpire Fergus Murphy and smashing two rackets.

The antics came just two weeks after he had tamed his wild ways to win the Citi Open in Washington DC, for his sixth career title.

"I've just been working really hard, on and off the court, to try and be better as a person and as a tennis player," he said at the time.

The good behaviour on display that week did not last long, leaving pundits and former players wondering whether the 24-year-old will ever embrace the change necessary to take his game to the next level.

"He has moments where he puts it together but even those moments are fraught with seconds or minutes of something happening that can completely set him off," former world number five Jimmy Arias, the director of tennis at the IMG Academy in Bradenton, Florida, told Reuters in an interview.

"I'm not Australian and it drives me crazy because you see how good he is. He would be a guy who could be number one in the world if he had anything upstairs.

"Even if he had half of (Rafa) Nadal's fight he would be top four in the world."

While prone to losing to modest opponents, Kyrgios often produces his best tennis when up against one of the 'Big Three' of Novak Djokovic, Roger Federer and Nadal.

He has a combined 6-9 head-to-head record against them -- 2-0 against Djokovic, 3-4 against Nadal and 1-5 against Federer.

"He can compete hard against (the Big Three) because there's no blow to his ego to lose," said American Arias.

"But if he is playing someone ranked a little lower, and he's obviously trying his hardest and he's losing or he possibly could lose, then he just goes in the tank and he's got that excuse for his ego.

"He's created a defence mechanism in his brain that he has to change and that's going to take work and I'm not too sure he's willing to do that work and I don't know it's that important to him in the end.

"The thing with today's players, he can try hard two for three weeks a year and still make a million dollars a year or something."

Former world number one Andy Roddick said he would be happy to have a career mulligan if he could be blessed with Kyrgios's gifts.

"His talent is unbelievable," the 2003 US Open champion told Reuters. "I would go back and play my career with his game in a heartbeat.

"We need there to be kind of a transcendent star. Like him or hate him, you watch him. I think for the good of the game (and) I'd like to see him deliver on his promise.

"I don't want him to be totally different from the way he is because the reason we're talking about him is because you can't take your eyes off him when he's on the court."

Kyrgios has shown little interest in taking advice, let alone the discipline of a coach, but Arias hoped someone could get through to him that a loss to a less talented player is still a loss.

"Someone should just say to him: 'Nick, when you tank, you still lost. It doesn't add any credence to your greatness'."