When Bjorn Borg left the 1981 US Open, having lost his second successive Grand Slam final to John McEnroe, few could have imagined what lay in store for the 25-year-old Swede. With 11 Grand Slam titles already under his belt and fitness not an issue, the master of Wimbledon and Roland Garros looked certain to overhaul Roy Emerson's record of 12 major victories.
It was not to be. Borg won on his next competitive appearance, a clay-court event in Geneva just a week later, but it was his last victory and he never played in a Grand Slam tournament again. The fire within him had died, despite an extraordinary record at the highest level which was showing barely any sign of slackening off: in his 16 Grand Slam tournaments between Wimbledon in 1976 and that US Open in 1981 Borg had failed to reach the final only twice.
Although he never returned to the Grand Slam stage, it was not until 1983 that Borg formally announced his retirement. He made some half-hearted comebacks over the next 10 years, but after a 13th successive first-round defeat, to Alexander Volkov in an indoor tournament in Moscow in 1993, when he was 37, the Swede finally put his rackets away for the last time.
Borg's case is a timely reminder to those who blithely assume that Rafael Nadal will go on to break the current record for Grand Slam titles, which now stands at 16. The mark was set by Nadal's great rival, Roger Federer, who failed to improve it when he lost in his 23rd Grand Slam final to the Spaniard at the French Open on Sunday. Six of Federer's seven defeats in finals – Juan Martin del Potro's 2009 US Open victory over the Swiss is the exception – have been at the hands of the current world No 1.
Nadal's 10th Grand Slam triumph, which saw him equal Borg's record of six wins at Roland Garros, leaves him in joint sixth place on the all-time list of champions alongside Bill Tilden and behind Federer (16), Pete Sampras (14), Emerson (12), Borg (11) and Rod Laver (11). Borg is the only player to have reached 10 Grand Slam titles in quicker time than Nadal, having done so when he was just one day younger at 25 years and one day.
Talk statistics to Nadal and he will push them back in your face, in the most polite fashion of course. Asked, in the wake of his latest triumph at Roland Garros, how he felt his record compared with Federer's, Nadal replied: "When you talk about these statistics, when you try and make these comparisons, really it's not very interesting to me.
"I'm very happy with what I have, with who I am. I'm not the best player in the history of tennis. I think I'm among the best. That's true. That's enough for me. I have a very high level of tennis. I am quite satisfied and very happy with what I managed to do. I'm very thankful for everything that's happened to me up until today."
Memories can be short and players' fortunes can rise as sharply as they can dip. When Novak Djokovic and Andy Murray reached the final of the Australian Open at the beginning of the year there was talk of a changing of the guard, of an end to the Roger and Rafa show. That was reinforced by Djokovic's extraordinary 43-match unbeaten run dating back to the end of last year, but when the world's top four players came together in the semi-finals in Paris last week it was the ancien régime that triumphed.
"I told people that we should wait six months after the Australian Open when people thought Rafa and me were done," Federer said in the wake of Sunday's final. "It's unfortunate that it goes so quickly at times. Now we're back in the finals and now it's different talk again. I don't even go there, because I knew it wasn't the case."
Nadal believes that the confidence he will derive from having retained his French Open title – he may also be feeling a sense of relief – will help him through the rest of the year, beginning with the grass-court season. The world No 1, whose victory ensured Djokovic would not replace him at the top of the world rankings, said that winning in Paris had in the past helped him through the next phase of the season. On the last two occasions he has won the French Open, Nadal has gone on to lift the title at Wimbledon; on the two before that he finished as the runner-up.
"After winning a title like this, you go there with a different attitude, with very positive confidence," Nadal said on Sunday night. "Winning here makes me play Queen's and Wimbledon with less pressure."
Given his past fitness problems, including the hamstring injury that scuppered his chances in Melbourne this year, what has been remarkable about Nadal's recent run has been his consistency. Although Djokovic got the better of him in four Masters Series finals after the Australian Open, the French was the seventh tournament in succession in which Nadal made the final.
Nevertheless, the very nature of the Spaniard's game casts doubt on how long he can maintain his current standards of fitness. Federer, who has an extraordinarily good fitness record, is an all-out attacking player who glides across the court and wins or loses his points quickly. Nadal, an aggressive counter-puncher who can turn breathtaking defence into stunning attack at the drop of a sombrero, plays a much more physical game and generally expends significantly more energy winning his points.
His knees have been suspect in the past and you wonder how soon they might prove to be a problem again. When he gets to Federer's age (29) it is hard to imagine Nadal avoiding injuries in the way that the Swiss has.
In the meantime, other challengers are likely to emerge. While Federer is closer to the end of his career than the beginning, Nadal's other main rivals are younger than him. Djokovic and Andy Murray both turned 24 last month, while Del Potro, who joined the elite group at the top of the game with his New York victory two years ago, is only 22. Even younger players, like the 20-year-olds Milos Raonic and Grigor Dimitrov, are breaking through.
Nadal, meanwhile, insists that chasing a place in the history books does not interest him. "Beating records is fine – it's perfect," the Spaniard said following his latest victory. "It's an honour to say that I have as many wins here as Borg, that I won as many titles here as he did. That's awesome. There was a lot of emotion.
"But the main satisfaction comes from all the work you did to get to this stage. You have difficult moments; you have wonderful moments. I work with a team which has always been very supportive. Without them, it would be impossible for me to be here today. It's all thanks to them."
Federer, similarly, said he had no interest in the fact that Nadal was closing in on his Grand Slam record. "Who cares where you stand?" Federer said. "It's when it's over that you can't do anything any longer. That's when you're proud of what you accomplished. That's why I'm happy for him that he's won these Grand Slams and these tournaments. He can prove to people that he can play a good type of tennis. This is what counts."
The Swiss added: "Ten Grand Slams is a lot. He knows this. I know this. Everybody knows this. It's really good for him."
Nadal in numbers
Nadal's 10 Grand Slams
2005 French Open (bt Mariano Puerta)
2006 French Open (bt Roger Federer)
2007 French Open (bt Federer)
2008 French Open (bt Federer)
2008 Wimbledon (bt Federer)
2009 Australian Open (bt Federer)
2010 French Open (bt Robin Soderling)
2010 Wimbledon (bt Tomas Berdych)
2010 US Open (bt Novak Djokovic)
2011 French Open (bt Federer)
Most major titles by the age of 25
11 (by 25) Federer so far, 16
11 Bjorn Borg career, total 11
10 Nadal so far, 10
10 Pete Sampras, career total 14
7 John McEnroe, career total 7
3 Andre Agassi, career total 8
2 Roy Emerson, career total 12