Roger Federer has revealed his most vulnerable state as he gave an emotional interview about his former coach Peter Carter.

Speaking to CNN from his training base in Dubai, Federer broke down in tears when he was asked about Carter, who was responsible for discovering the tennis legend in Basel when he was only a teenager.

“It’s a really nice story,” said Federer. “He came to play club tennis for my club in Basel, Old Boys Tennis Club. When I was little, he was one of the star players on the team. I was able to have coaching lessons with him.

“Peter was a really important person in my life. If I can say thank you for my technique today, it’s to Peter.”

Sadly, Carter passed away in 2002 after he was involved in a car accident in South Africa during his honeymoon.

He died a year before Federer won his first grand slam at Wimbledon.

When asked what Carter would think about the athlete’s career if he was still alive, Federer was reduced to tears.

“Sorry. Oh, man, I still miss him so much. I hope he would be proud,” he said.

“Geez, never broke down like this,” he later said.

It was revealed in The Roger Federer Story: Quest for Perfection – a book about the tennis champions life by journalist Rene Stauffer – that Federer “was never so upset in his life” when he heard the news of Carter’s death during the Canadian Masters in Toronto.

According to an Australian newspaper, the 37-year-old left his hotel and “ran through the streets, bawling and hysterical.”

Federer told CNN that the moment was a turning point in his career saying: “He didn’t want me to be a wasted talent. It was somewhat of a wake-up call for me when he passed away, I really started to train hard,” he said.

“I’ve been incredibly fortunate to have the right people at the right time, the right coaches at the right time. Sure, I make those decisions but I’ve been lucky along the way.”

Federer has proven his loyalty to Carter as he is regularly seen paying for Carter’s parents to travel from Adelaide to Melbourne to attend the Australian Open every year.

The Swiss player is determined to take home the title this year.

“Am I confident? I don’t know. I feel good. I’ve been training really well. I’ve had another great year. Still happy playing and I’ve won the last two Australian Open editions, so I should be going in there with confidence,” he said.

“I love playing Australia, love playing in Melbourne. There’s so much that connects me to that country. The legends that I admire, the coaches that I’ve had in Tony Roche and Peter Carter – they’ve been incredibly inspirational and important to me in my life.”

The Australian Open will commence on January 14 and will air on Channel Nine.