That's according to former world No1 Mats Wilander who expects Federer to prolong his career in a bid to hold off the Spaniard and remain top of the all-time Grand Slam charts.
Nadal won his 19th major on Sunday, beating Danniil Medvedev in an epic five-set final at Flushing Meadows to put himself within touching distance of Federer's record tally of 20 Slams.
It is the first time since 2004 that Nadal has closed that gap to just one, with the Spaniard expected to add to his tally at least once before the third Grand Slam of the year at the All England Club in July.
“I am excited about the next two or three years,” Wilander told Eurosport.
"Federer will try to stop Nadal, it will encourage the Swiss to play for at least two more years."
At 36, Federer became the oldest ever world number one in 2018 and, now into his 39th year, continues to fight for the sport's top honours.
Though he has not won a major since January 2018, the Swiss was within one point of a record ninth Wimbledon title in July and has set his sights on more glory in the coming years.
At the US Open, Federer was asked if he will still be playing at 40 years old.
“A few years ago, I wouldn’t have thought that could be possible," he said.
But when you feel fully fit like I do right now, you think you can play forever.
“I see it as a privilege to feel like that for a longer period of time. I haven’t had any major setbacks since I felt my back in Montreal against Sascha Zverev (in 2017).
“I had a few little things, but nothing career-threatening. If I feel like that, I can play more freely, concentrate on my tactics and enjoy my off days much more.”