Roger Federer shares a picture with tennis legends

Serena Williams played what was likely her final match three weeks ago at the US Open, and Roger Federer was watching along with the rest of the crowd.

"I'm not shocked. Simply so much like myself in many aspects. "Serena-caliber athletes shouldn't ever consider retiring. Just a terrific career, I thought."

He understands that some tennis fans would abandon the sport as a result of their back-to-back retirements after approximately a quarter-century each — he is 41 and retires with 20 grand slam titles, and she is 41 on Monday with 23 major singles victories.

But Federer is adamant that a lot of people will remain.

In an interview at the Laver Cup, where his final match of his illustrious career will be in doubles with rival Rafael Nadal for Team Europe at about 5am AEST, We might lose some people because they decide to go on to another sport or athlete after saying, "OK, that chapter is closed for me.

"And some will devote their lives to the sport due to the reason is tennis is one of those sports where once you get engaged, you usually keep involved. Because of this, I don't think many people will depart."

Federer tweeted from London's Thames, where he was taking a selfie with Andy Murray, Rafael Nadal, and Novak Djokovic before the Laver Cup, saying, "Heading to dinner with some pals."

It served as a sobering reminder of the tennis talent that is waning.

Federer and Williams, together with Nadal, 36, who has a men's record 22 slam championships, and Djokovic, 35, who has 21 titles, all contributed to the development of a golden era in the sport that attracted new fans and motivated young athletes.