Published 14/09/2017 at 08:58 GMT | Updated 14/09/2017 at 10:32 GMT
Despite winning the French Open and US Open in 2017, Nadal remains three majors adrift of Federer, who added the Australian Open and Wimbledon to his overall haul as the world's leading two players split the season's majors between them.
Nadal would have been only one behind Federer if he had not lost to the revitalised Swiss player in Melbourne over five sets back in January.
Rafael Nadal of Spain in a training session with coach and uncle Toni Nadal
The Mallorcan is back at number one in the rankings and is likely to end the season at the summit having won a 10th French Open at Roland Garros and a third US Open at Flushing Meadows where he crushed Kevin Anderson in the final on Sunday. Having last won a major in 2014, it has been a dramatic return to form for Nadal.
Nadal will turn 32 when he bids for an 11th French Open in Paris in June, and will be strongly fancied to contest all of the major next season as Uncle Toni, who will return to grassroots coaching when the season ends, points out.
We will get to Federer’s 19, yes. I think it will happen. It’s difficult, but there is some more Roland Garros and I am confident other titles will come.
"When he was 12, 13 or 14, you never think he will get to this level," he said.
I am very happy to see my nephew lift so many trophies, knowing that he has achieved another piece of history. He has won a hard-court tournament for the first time since 2014. We are very happy that he has won another Grand Slam, his 16th, and is in a position to fight for number one.
Roger Federer and Rafa Nadal
Image credit: Getty Images
"It was unimaginable that would happen, of course. But I had faith that Rafael would win one more Grand Slam, I tell you truthfully."
Do pundits agree with Uncle Toni?
Yes - Mats Wilander (Seven-times Grand Slam champion)
I think that Nadal has a very good chance to catch Roger because he’s gonna win the French Open again at least once or twice and suddenly you’re one or two away. Do we think that Federer is going to win another slam next year when he turns 37? I don’t know. He can win another one maybe, but Nadal has another four or five years and people are wrong when they think that he’s physically wearing himself down.
Yes - Jim Courier (Four-times Grand Slam champion)
It could be 18-17 right now and if Nadal stays healthy, he’s going to have significantly more opportunities than Federer just because of the age gap. Who’s going to bet against Nadal winning a couple more French Opens if he’s in good health? Not me. That’s for sure. This is a story that’s still ongoing, they’re very much in motion. ‘One of the big questions for 2018 is which Novak Djokovic shows up. Hopefully he’ll be healthy. He could very likely get himself back in the mix as well.
No - Pat Cash (1987 Wimbledon champion)
Take away the French Open and Federer is the best all-round player in the world. There's no doubts about that. He's my favourite for everything apart from the French. As long as he's fit, he's favourite for the Australian, Wimbledon and the US Open. Will he catch Federer's record? I don't know if he even cares about that. We get obsessed by the numbers thing; it's a whole hype thing. He's just happy to be out here and competing and if he gets near Federer.
Our view: History firmly against Nadal
The assumption that Nadal will win another one, two or three Grand Slams is based on the belief that the next few years will mimic this year, and that he also stays clear of injury. Such predictions are hardly set in stone with form and fitness as dependable as the weather in Wimbledon.
If we have learned anything from the past 12 months in tennis, it is difficult to make any predictions without being made to sound foolish. If you predicted less than a year ago that Federer and Nadal would be carving up the Grand Slams as their own personal property in 2017, you would have prompted widespread guffawing.
But a renewed zest and hunger to impress has coincided with the decline and demise of Novak Djokovic and Andy Murray, two former world number ones who have been decimated by a loss of form and a loss of fitness. Djokovic has called time on his season due to an elbow problem with Murray likely to do likewise due to a hip injury.
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Nadal's quest for 19 Slams is likely to depend upon two things: his fitness entering his 32nd year, and also how his rivals fare in 2018. With Stanislas Wawrinka likely to return refreshed from a knee problem that prevented him from defending the US Open, plus Murray and Djokovic potentially firing again, it is far from straightforward that Nadal will make it to 17 never mind embarking on the jump to 19. He is unlikely to encounter another Grand Slam like Flushing Meadows that he won without facing a man inside the world's top 20.
There is as much chance of Federer winning a 20th Grand Slam, probably at Wimbledon, as Nadal winning another French Open.
Much is made of the five years he has on Federer, but again this is misleading because it is not comparing a 21-year-old Nadal to someone aged 26. Apart from Federer this year, only three men in the history of the sport have lifted Grand Slams beyond the age of 32. Andre Agassi was 32 when he won the last of his eight majors at the Australian Open in 2003. But you would have to go back to the 1970s when men like Andres Gimeno was 34 when he carried Paris in 1972, and Aussie Ken Rosewall was setting record at the outset of the Open era in the sport.
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Rosewall won the French Open at 33 in 1968, the US Open in 1970 and back-to-back Australian Opens in 1971 and 1972 respectively, the last of which made the oldest Grand Slam winner of all time at the age of 37. That remains a target for Federer before he retires, and is likely to become a viable number as he bids to put more space between him and Nadal in the GOAT race.
It is hardly impossible for Nadal to reach 19 when he is so dominant on clay, but we should not ignore the fact that Federer went five years without a Grand Slam between Wimbledon in 2012 and Melbourne this year. Winning a Grand Slam is difficult, winning three more in your 30s still remains a huge ask even for Nadal's considerable powers.
History suggests Federer is already safe on 19.
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