Novak Djokovic says he does not “know on what basis” three-time Wimbledon champion John McEnroe likened him to golf star Tiger Woods.
Djokovic, 30, has lost all four Grand Slam titles which he held last year and slipped to fourth in the world.
Woods, a 14-time golf major winner, has struggled for form after marital problems and injury in recent years.
McEnroe said Djokovic “had some off-court issues with the family”, but the Serb said he took the claims “lightly”.
“He’s well known for his bold comments and not caring too much about being politically correct and saying whatever is on his mind,” Djokovic said about American McEnroe.
“I don’t take anything personally.”
Djokovic, a 12-time Grand Slam champion, said last month that 2017 had been his toughest year in tennis.
As well as losing all of his major crowns, he slipped out of the world’s top two for the first time since 2011 and split with his coaching team.
However, the former world number one has rediscovered his form during the grass-court season.