Roger Federer has a strong claim as being the greatest tennis player of all time.
The 36-year-old's 20 Grand Slams are the most of any man to ever play the sport and after winning the 2018 Australian Open, it seems likely he will get at least one more Grand Slam before walking away from the game.
However, when speaking with Jason Gay of The Wall Street Journal, Federer explained how one of his contemporaries needs to be mentioned in the GOAT conversation.
"It's been fascinating to watch," Federer said to Gay about the rise of Serena Williams in comparison to his own ascendance in the world of tennis.