Novak Djokovic's father has launched a stinging attack on Roger Federer and Rafael Nadal - implying the two men are jealous of his son's success.
Djokovic has overtaken both men to became the highest ranked player in the world and his father Srdjan says he has noticed Federer and Nadal's attitude to Djokovic change over the years as his son became more successful
"Federer is perhaps still the best tennis player in history, but as a man he's the opposite," Srdjan told Serbian newspaper Kurir.
"He attacked Novak at the Davis Cup in Geneva (in 2006), he realised that he was his successor and was trying to disparage him in every way. Novak's success is an amazing thing and something that Federer cannot understand."
He was similarly critical of Nadal saying: "He was his best friend while he was winning. When things changed, they were no longer friends. This is not sport."
Djokovic Sr did at least have some kind words for Andy Murray, who beat Djokovic in the Wimbledon final earlier this month.
"I have never, not even for a second, felt jealousy from Andy's family. They cannot be best friends as they fight for the most important titles, and (a) lot of money, but they approach their rivalry in the correct way," he said.
Between them, Djokovic and Murray have won seven of the last 11 Grand Slam titles.
Over that period, Nadal has won three French Opens with Federer's success at Wimbledon in 2012 being his only Grand Slam triumph over the past three seasons.