Wimbledon 2015: Dawn Fraser accused of 'racist attack' on Nick Kyrgios

Kyrgios, 20, was booed by the crowds in London on Monday when he apparently stopped trying to win after being repeatedly chastised by the umpire in his fourth-round match against France's Richard Gasquet.

In what commentators condemned as "another petulant performance," the Australian got into trouble for swearing, then argued with the referee over whether he was taking too long to change his socks, and bizarrely hugged a ball boy before eventually losing the match 7-5 6-1 6-7 (7-9) 7-6 (8-6).

He was fined $2,000 for swearing, but escaped sanction from tournament organizers for his other actions.

Asked what she thought of Kyrgios' conduct, four-time Olympic champion Fraser told Australia's Today show: "I think it's absolutely disgusting."

The former swimmer accused Kyrgios and fellow player Bernard Tomic -- who was dropped from their country's Davis Cup side after a verbal attack on tennis officials -- of un-Australian behavior.

"I am so shocked to think that he went out there to play and he tanked, he did all that tanking. That's terrible, that's not a good Australian sportsperson," the 77-year-old said, accusing today's athletes of having "too much money at an early age" and of listening to bad advice.

"They're a disgrace for Australian sportsmen and women. They should be setting a better example for the younger generation of this great country of ours. If they don't like it, go back to where their fathers or their parents came from. We don't need them here in this country to act like that."

Kyrgios retaliated by calling Fraser a "blatant racist" and posting a link to the interview on Twitter and Facebook.

Kyrgios was born in the Australian capital, Canberra, to a Greek father and a Malaysian mother. Tomic, meanwhile, was born in Germany and his parents are from the former republic of Yugoslavia.

Kyrgios' mother Norlaila, known as Nill, stepped up to defend her son, saying Fraser's "nasty racist attack" was "out of line."

Fraser later offered an apology for her comments, insisting they were made on a "purely sporting level, rather than meant as an attack on Nick's ethnicity."

"I want to unreservedly apologize for any comments that I made this morning which may have caused offense to my fellow Australians including Nick and his family," she said in a statement reported widely in Australian media.

"Nick's representing Australia and I want to see him representing Australian tennis in the best possible light."

Fraser was the first female swimmer to win gold medals at three successive Olympic Games -- 1956, 1960 and 1964 -- and broke the world record in the 100 meters freestyle nine times.

Kyrgios was hailed as a rising star of tennis last year when he defeated then world No. 1 Rafael Nadal in the fourth round at Wimbledon.

But he has since earned a reputation as one of the sport's "bad boys," frequently finding himself in trouble with match officials after swearing and arguing with umpires and line judges when unhappy with his performance or with calls that go against him.

At the same time, he has thrilled crowds with his extravagant shot-making and aggressive approach on court.

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