It was the making of Mary Pierce but the breaking of Jelena Dokic.
Now only time will tell what impact the seemingly inevitable long-term banishment of John Tomic has on Bernard Tomic's turbulent tennis career - and life.
For all his notoriety - the volcanic temper, the irrational outbursts, the heavy-handedness and the disrespect for officialdom and former world No.1s - John Tomic has maintained his place front and centre in Bernard's camp.
"Since I started at age eight he was there by my side," Tomic said in happier times after landing his maiden ATP Tour trophy in Sydney in January.
"We did do a lot of hard work together. Growing up, he was the main thing, the main person that was always behind me ... for me to win my title, have my dad by my side, was amazing. It was a huge feeling.
"He is for me the best coach. That's why I've always had him by my side and always will continue to have him there to support me."
Certainly not now and, if officials have their way, perhaps not ever again - not as coach anyway.
The ATP have already suspended John Tomic indefinitely while they investigate the allegation that he assaulted Bernard's training partner Thomas Drouet, leaving the Frenchman heavily concussed with a broken nose and damaged vertebrae. He has claimed self defence.
Drouet has since also claimed that John, a Croatian-born former taxi driver driven by the dream of Bernard becoming world No.1, also hit his son two days earlier during a practice session.
Asked for comment from John Tomic on that allegation, Tomic's manager Fraser Wright told AAP they could not respond before his next court appearance in Madrid on Tuesday on the charge of assaulting Drouet.
Bernard Tomic visited his battered hitting partner in hospital in Madrid this week.
"He told me: 'I'm sorry. He went too far. It's over. I don't want him to come to tournaments anymore'," Drouet told L'Equipe newspaper.
Despite his previous public support for his father, indications of this moment have been coming for more than a year.
In March last year, Bernard asked an umpire in Miami to remove his distracting dad from the side of the court during a match against David Ferrer.
Then after losing in the first round at Wimbledon in an uncharacteristically ill-tempered display, Bernard confessed to not training hard enough amid speculation he no longer wanted his father as coach.
"There's also a few other things that are involved, also last few, eight weeks, which I can't talk about," Bernard said when asked if John had been frustrated or annoyed by his lack of application.
The Wimbledon meltdown came during a horror run of six straight first-round defeats before John McEnroe accused Australia's two-time grand slam junior champion of tanking against Andy Roddick at the US Open.
Bernard angrily denied giving up, but five weeks later admitted to only putting in "about 85 per cent" in a 6-4 6-0 first-round loss to Florian Mayer in Shanghai.
As Bernard turned 20 the following month, his father's audacious hopes of three years earlier for his prodigiously talented son to win "10 to 15 grand slams" appeared even more outrageous.
But as he tumbled out of the world's top 50 - after reaching a career-high No.27 last June - and feeling his career slipping away, Bernard "had a conversation with myself" and resolved to reverse his fortunes.
He decided after calling a premature end to a forgettable 2012 campaign to build "the best team possible" around him.
Central to that team were John Tomic and Thomas Drouet.
"That was in October last year," Bernard said amid a 10-match winning streak over the Australian summer.
"I said: 'Look, time's flying. I do have the talent. I can play good. But I'm not using it'.
"So I worked hard, as much as I could. It's amazing what can happen in two months, let alone in the next year if you push yourself to improve every day.
"... Thomas is hitting with me and helping with me and my dad is running everything, coaching me.
"It's just a team now that everyone is happier. I know what I want. That's the main thing. I've got great people around me who are helping me now."
But now that close-knit team appears in ruins and John Tomic is facing a possible lifetime ban from the ATP Tour as well as the WTA Tour, where Bernard's promising 15-year-old sister Sara is headed.
Following the lead of the men's tour, the governing body of women's tennis are wary, having already rid themselves of a clutch of domineering and so-called bad dads, most notably Jim Pierce and Damir Dokic.
Pierce prospered to win two grand slam crowns after her verbally and physically abusive father was prohibited from attending any tour events after, among other infamous incidents, attacking Mary's cousin and once screaming "Mary, kill the bitch" at a junior tournament.
Dokic, though, struggled after her father and coach lurched from one controversy to another before finally being estranged from his daughter and serving jail time in 2009 for threatening the Australian ambassador to Serbia with a hand grenade, causing public endangerment and for illegal possession of weapons.
A Wimbledon semi-finalist at 16 and former junior world No.1, Dokic's career was all but done before her 21st birthday.
Her troubled compatriot Bernard Tomic turns 21 in October.
And with his career once again at a crossroad, Australian tennis greats are rallying around the country's brightest hope.
"The key for us in this whole thing is making sure that Bernard's welfare is being taken care of," said Tennis Australia's head of men's tennis, Todd Woodbridge.
As John Tomic awaits his fate and his Madrid court date on Tuesday, Woodbridge, Tony Roche, Pat Cash and Davis Cup coach Josh Eagle have all offered to mentor Bernard in the lead-up to the French Open and Wimbledon in the coming two months.
Bernard, though, may find his greatest ally in himself.
"Regardless of who's working with me, it's my sort of tennis - my game, it relies on me," he said last year during a similarly unsettled time.
"People can say they can help you with a lot of tips. Even my dad who has been with me for 11 years has done a great job ... but saying people can help, it's not really. For my tennis, it's all about me. I've got to find that in me.
"People give you great tips along the way and can help you and stuff, which I'm ready for any help, but you're not going to become Federer, Rafa or Novak if you don't do it yourself."