The tragic accident that changed the trajectory of Roger Federer's life.

We applauded Nick Kyrgios earlier this week for congratulating his opponent after losing to Grigor Dimitrov in the Australian Open.

It was an unprecedented show of sportsmanship from the 22-year-old Greek Australian from Canberra. “Maybe he’s changed,” news headlines surmised, highlighting the difference in behaviour compared to his typical racket-smashing, temper-tantrum displays.

Kyrgios and 25-year-old Bernard Tomic, and many others who’ve come before, are just as known for their talent with a racket as they are for their antics in-between matches, or off the court entirely.

This bad-boy persona puts them worlds away from the perceived real pros. The likes of Swiss world champion Roger Federer, for example, who is renowned for his calmness, flawlessness even, as a sportsman and professional.

But, in our haste to love-to-hate the Kyrgioses and Tomics of the arena, it appears we are forgetting history.

Now, it’s been reported, Federer, too, was once a “brat” who blasted loud music while his coach was in the car, and had “too much energy” for others to handle.

Former communications manager at the Association of Tennis Professionals (ATP) David Law, who met Federer when he was 16 and helped him prepare for interviews and press appearances, has shared a side of the 36-year-old 19-grand-slam-title winner that we never saw coming.

"The number of times we would go to tournaments and he would throw in a substandard performance where he’d mentally break down or he’d get emotional and throw his rackets — he was a baby," Law said on his podcast, News Corp reports. "Honestly, he was a crybaby on the court."

Law said Federer was lazy and carried an attitude that came from knowing he was talented. The first time Law practiced with him, he said, he thought 'wow' - not at Federer's skill but because the then 16-year-old didn't seem to care at all.

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Federer's coach at the time, Peter Lundgren, also had a tough time with the budding champion, Law explained.

"I know Peter Lundgren used to take him out in a hire car in Miami and they’d stick on AC/DC and Federer would sing it and shout it at the top of his lungs," Law said. "People don’t realise what an exuberant character Roger Federer is, how loud he likes to be."

"In the locker room and the showers he’d be screaming at the top of his voice doing impersonations of other players and characters that he might have seen in the World Wrestling Federation and things like that just because he had so much energy."

What was the turning point? From this over-energised boy who was apparently arrogant, lazy and self-entitled?

According to Law, it was the shocking death of Federer's former coach, Peter Carter, who coached him from age nine to 18, in a car accident in 2002 that pushed Federer to change his ways.

"Federer was devastated," Law said. "That made Federer grow up incredibly quickly because I don’t think he’d ever had to think about mortality before.

"It stopped him in his tracks and it caused him problems for a long time in terms of dealing with it, dealing with the grief. This is someone he knew well, who he saw every day, who he travelled everywhere with."

It's a story that makes Federer's demeanour today even more impressive. This is a hero who could have been someone else entirely. Indeed was someone else entirely, until he made the decision to change his life amidst ferocious grief.

It's also a lesson to the rest of us.

A lesson perhaps, to treat the younger players, those who appear to let fame and money fuel their egos and arrogance, with a little more compassion. Remembering Federer's meltdown came before the age of digital media where headlines follow players everywhere. Remembering there is so much more going behind the scenes than we can possibly know. Also remembering the man Federer has become, from the person he once was.

Hopefully, some of those younger professionals rising in Federer's shadow might make a similar transformation, only without such a harrowing push in the right direction.

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