Federer's pulling power was demonstrated again by full houses and blanket coverage of the Laver Cup in London, where there were tears all round as he bade farewell.
Here, we assess what comes next for the men's game.
How much will Federer be missed?
The 41-year-old is not just arguably the most popular tennis player of all time but one of the most popular sportspeople. It is undoubtedly the end of an era but Federer has played very little over the past two and a half years so his absence on court is in many ways the status quo. The key for tennis will be ensuring Federer remains associated with the sport as much as possible.
How will he stay involved?
That remains to be seen, although he already has his finger in several pies through the Laver Cup, which was his brainchild, and the Team 8 management agency he set up with his long-time agent Tony Godsick. Wimbledon and the other grand slams will surely want to throw him farewell parties while he has already suggested he might try his hand at TV work but has ruled out getting involved in the messy management structure of tennis.
Who's top dog now?
Rafael Nadal takes over as the leading elder statesman of the game but, despite winning two grand-slam titles this year, major question marks remain over his long-term physical capabilities. Novak Djokovic's biggest opponent this year has been Covid-19 vaccination rules and it would be a surprise if he did not return to the top next year while Carlos Alcaraz's ascent to world number one has been a timely boost of excitement for what is to come.
Can Alcaraz carry the sport?
Trying to follow in the footsteps of Federer, Nadal and Djokovic is clearly extremely daunting. Alcaraz is only 19 and so many things can derail a career but there is no doubt the Spaniard is a special talent. He proved in winning the US Open that he already possesses everything needed to succeed at the very top with the promise of more to come, and he has an X factor on court that can attract new fans to tennis.
Does he have competition?
The fact Federer, Nadal and Djokovic all pushed each other was a key factor in this golden era. There are certainly other names in the frame to challenge Alcaraz, starting with 21-year-old Italian Jannik Sinner, who held match point against the Spaniard in the best match of the US Open. Frances Tiafoe is another terrific crowd pleaser and, like Casper Ruud, Stefanos Tsitsipas, Felix Auger-Aliassime, Holger Rune and Lorenzo Musetti, is under 25.
What can we expect in 2023?
An interesting question. Despite Alcaraz standing at number one, Nadal will probably be favourite for the French Open again and Djokovic for the other three slams. But it would no longer be particularly surprising if the tournaments do not play out that way. The US Open showed that the new generation can carry a slam by themselves and they will need to keep doing it for they have the biggest shoes to fill.