With age such a talking point when it comes to Federer’s tennis career, the eight-time Wimbledon champion says he now feels far away from his 20s.
He holds a number of achievements in relation to his age, becoming the oldest ever world No 1 in February 2018, at the age of 36 years and 195 days.
Federer is also the second-oldest ever male Grand Slam champion, winning his 20th Major at the 2018 Australian Open when he was 36 years, five months and seven days old.
The Swiss tennis ace admitted: “Suddenly you’re 40 and you think: “Hey, no, unbelievable!” I suddenly feel very far away from my 20s. I was just a child back then.
“Now at 40 I feel like I have to be more serious. You used to look at 40-year-olds and they were mega old. Now suddenly I’m one of them too.”