Not long before Andy Murray was looking heavenward in exultation and disbelief in the Arthur Ashe Stadium 12 months ago, Rafa Nadal was uttering silent prayers as he sat in Dr Angel Ruiz Cotorro's medical practice in Barcelona.
Nobody knew whether the partially-torn patellar tendon in the Spaniard's left knee, which had hindered him during his shock Wimbledon collapse to Lukas Rosol and kept him out of the Olympics and the US Open, would require an operation and concerns were being uttered about whether he would ever be the same player again. In the end, no further surgery was required, but those predictions proved correct: he never was the same player again. On the evidence, of the last month or so, he is even better.
Of the 56 matches the 27-year-old has played since his return to the tour, the Spaniard has lost just three, none of which have come from his 15 matches on the hard courts. Of course, one of those was in the first round at Wimbledon against Steve Darcis, but that is the only real blip in a season which has harvested nine titles, including a record eighth victory at Roland Garros.
But it is his sudden supremacy on the hard courts of Montreal and Cincinnati which is most startling, considering this is a player who followed up his 2010 US Open win by going the 30 calendar months between October 2010 and Indian Wells this March without winning a single tournament on any surface other than clay. No wonder much of Murray's thunder, as well as his world No 2 ranking, has been stolen, as he prepares to defend a Grand Slam title for the first time.
Compared to the stunning brilliance of the Spaniard's season, the consensus amongst the world's top pundits is that the form of the other leading lights of the men's game has diminished. Murray, for instance, has followed up his triumph at his home slam with a holiday in the Bahamas and a couple of slip-ups against Ernests Gulbis and Tomas Berdych, world No 1 Novak Djokovic's early season excellence has turned into high-profile frustrations against the likes of John Isner, while Roger Federer arrives at Flushing Meadows with the ignominious ranking of world No 7.
As of last week Nadal boasts a winning record against every player in the world's top 30, including a 13-5 advantage against Murray, 21-15 against Djokovic, and 21-10 against Federer. Just as at SW19, the Swiss is the Spaniard's potential quarter-final opponent if he manages to find a route through the tournament which may include Fernando Verdasco, Isner and countryman David Ferrer.
"If you go back to his record this year, the few matches he's lost, including hard courts, is a huge surprise," said Cliff Drysdale, the veteran ESPN pundit who recently took his place in the tennis Hall of Fame. "Notwithstanding the great play of Andy Murray and the fact he won Wimbledon, in my book he would have to be No 2 behind Rafa in the stakes for the US Open this year just based on that outstanding hard-court record and the fact he seems to be physically fit and physically able to perform. I think at this point Nadal is the best player in the world.
"I've learned to respect Murray's game tremendously in the last 18 months and I think he's taken care of some of those psychological devils that used to be so much a part of his make-up. But his game, I would not put on the same level.
"I don't think any of us felt Rafa wasn't going to be a contender on anything but clay because he previously won Wimbledon. But he has become more aggressive. His vulnerability was always that with so much top spin, eventually he would hit a short ball. He's corrected a couple of those things on the hard court. He's not as far back as he used to be and he's flattened his shots out, albeit not by much. That puts more pressure on his opponent and that's why he's a better hard-court player than he used to be."
With 12 Grand Slam titles in his possession by the age of 27, the Spaniard may be regarded one day as the best ever, says Drysdale's ESPN stablemate John McEnroe.
"I would just say that we're all extremely pleased for our sport that he's come back seemingly so healthy," McEnroe said. "I rate him as one of the all-time greats and there is an argument to make him 'the' greatest with his results and head-to-heads with these other top guys. I was concerned after watching him at Wimbledon, but maybe it was a blessing that he had an extra couple of weeks. This would be the perfect schedule for him so he's just where he wants to be. It is going to be really exciting now. You've got three guys, one major each for Rafa, Murray and Djokovic, going for the No 1 ranking. It should be an outstanding and exciting Open."
Slighted by his absence from that list is Federer, ranked only now in the second rank of challengers, albeit amid such dangerous big hitters as Berdych and resurgent 2009 winner Juan Martin del Potro. In the last month, Federer has experimented with a larger sized racquet, only to revert to his old one for Flushing Meadows.
"I think one of the things you notice is possibly he's slowed down a little bit," said McEnroe. "The balance and the movement are not quite as Nureyev-like as they were in the past. So he's reaching for more balls and therefore mis-hitting more shots. It doesn't seem like he's been able or willing to make that adjustment where he's got to either play safer or take that extra step to balls."
McEnroe for one doesn't fancy Federer's chances of shocking the world with a recovery. But then people were saying precisely such things about his Spanish heavyweight rival 12 months ago.