• Roger Federer will be in action Tuesday in Geneva Open
  • It will be Federer's second tournament in 2021
  • Serena Williams is currently playing in the Emilia-Romagna Open, Parma

There have been never-ending debates to determine who among Roger Federer, Rafael Nadal, and Novak Djokovic is the greatest of all time. 

Nadal equaled Federer’s 20 Grand Slam titles by clinching the French Open last year, while Djokovic is at 18. Federer seems to have got Serena Williams’ vote as she hailed the Swiss Master Monday, calling him a "genius."

Williams defeated 17-year-old qualifier Lisa Pigato 6-3, 6-2 Monday in the first round of the Emilia-Romagna Open, Parma, which was her first victory in more than three months.

In a post-match interview with ATP’s official website, Williams heaped praise on Federer, who is set to play his second tournament of the year this week since returning to the tour in March after spending more than a year on the sidelines due to two knee surgeries. Federer will be in action at the Geneva Open on Tuesday.

“I think two words sum it up: Roger Federer. He’s just a synopsis of greatness and class and amazing and really changed the game. You see players playing like him, moving like him, doing his techniques. The guy is [a] genius,” Williams told ATP’s official website of Federer’s legacy.

In the same interview, the 23-time Grand Slam winner also admitted that she is a "superfan" of Federer.

"I just feel like he is really the greatest player. Just look at him. You can’t not like the guy, that’s how I feel. His game is so fantastic. If I could only play like him!" added Williams.

Roger Federer and Serena Williams Roger Federer and Serena Williams have dominated their respective circuits in tennis for over a decade. Photo: Getty

Williams, who is still chasing her 24th Grand Slam title, was eliminated after losing the first round at the Italian Open last week. The American ace then accepted a wild-card invitation for the Parma tournament and dominated her opponent in the opening round Monday.

"I’m just starting to feel more comfortable. I’ve always felt super comfortable on the clay and this year has been a little more difficult than normal. I think it was because of the long hiatus I’ve had (from) the clay," said Williams, who produced six aces in the game.