When David Letterman lured Rafael Nadal on to his late-night TV show in New York this week, he put it to the Spaniard that his rivalry with Roger Federer was the one that has defined his career, the one that made him the great player he is today.
Nadal had a book to plug. He grinned in the heat of the studio lights and, forced to look upwards at Letterman on his raised pulpit behind a ludicrously large desk, he looked lost. "Bjorn Borg – you've heard of Bjorn Borg," the host said, in the patronising tone talk-show hosts reserve for visitors with funny accents, "and John McEnroe, they had that rivalry that made both of them great. Do you and Federer have that same chemistry, that same dynamic to make one another greater?"
Fighting his urge to talk plainly, Nadal trimmed his answer to suit a question that was out-of-date and, in terms of who might win the 2011 US Open, irrelevant. "I don't know," he stuttered. "Every rivalry is completely different. McEnroe and Borg had fantastic rivalry. Federer and I, we [have had] a lot of matches the last couple of years. It's exciting, emotional but, at the same time, we have very good relationship … " "But, without him," Letterman cut in, "would your tennis be as good today?" "Uh … probably not," said Nadal, hesitating. "Some times it is better if he is not there!"
Federer is there, of course. He always is, an ever-present in grand slams, the 30-year-old Swiss of effortless genius, whose longevity is as intriguing as is Nadal's tenuous grip on his failing body.
What Nadal was trying to tell Letterman was that he is no longer measured alongside the player with whom he shared a seven-year hegemony in men's tennis. Nobody talks about their rivalry any more. Federer has not won a major since February 2010, in Melbourne, and the player to whom all others look now in any draw is Novak Djokovic. At Flushing Meadows, they might even not be looking that closely at Nadal, who is nursing a foot injury and blistered fingers from a cooking accident in Cincinnati.
Yet it has still to sink into the passing consciousness of an audience entertained by the likes of Letterman and other tennis tourists that the old order has changed. There are, by general consensus, only four players with a chance of winning this title when the hurricane eventually passes: Nadal, Federer, Djokovic and Andy Murray. But a closer inspection of their individual rivalries, informed by recent form and fitness, suggests the seedings and the bookmakers might have miscalculated as badly as Letterman.
Nadal is headed for a semi-final against Murray, unless one or the other is tipped out by the impertinent challenge of supposedly lesser players. Presuming they meet, Nadal will be favourite because, on the face of it, their looks to be an uneven one. The Spaniard, a year older at 25, has 10 grand slams, Murray, famously, none. Nadal leads Murray 12 wins to four overall, including their past four meetings, stretching back to 2007.
Yet Murray will assert at every tournament that the player he enjoys playing most is Nadal. It inspires him to test his tennis at a much higher level than he will experience, for instance, against the lightly-regarded Indian Somdev Devvarman in the first round, or Feliciano López, whom he has beaten five times in five matches, in the second.
Murray is more concerned with road-block opponents, good players who, according to the odds-makers, provide stubborn, dangerous resistance but are not favoured to go deep into a grand slam tournament – such as Stanislas Wawrinka, who put Murray out in the third round last year and is lurking on his side of the draw again.
"I heard that the draw was a nightmare," Murray said. "But it happens. Sometimes there are guys you never seem to play against and then there are guys that you draw in your section pretty much all the time. I've been in Wawrinka's section probably four times now at the US Open. "
Murray also sees quite a lot of Nadal. In 16 grand slam events, they have been on the same side of the draw 15 times. Even given that, for much of that time Nadal was No 1 in the world and Murray was at 3 or 4, where he currently resides, that is a remarkable recurring theme. Nadal most recently beat Murray at Wimbledon, in the semi-finals. Before that, it was the same stage of Roland Garros; before that it was the same stage at the ATP World Tour finals in London last year.
It is a wonder Murray does not hate the sight of him, but it is the only way – as Letterman would have it – he can define himself. Nadal is the player Murray judges himself against, not so much Federer, against whom he has an 8-6 record, although the world No3 clearly remains a significant barrier to his advancement. The other part of the equation is Djokovic, the world No1, the favourite.
Murray would relish a final against the Serb. He beat him in Cincinnati, joining Federer as the only player to get the better of him in 59 matches this year. And he knows Djokovic is vulnerable, his injured right arm still a liability. All in all, he is happy enough with this draw.