There is probably nobody in the modern game who can improve over the course of a Grand Slam tournament better than Rafael Nadal. Twelve months ago the Spaniard arrived here at the US Open concerned by his form and with his serve looking particularly vulnerable. A fortnight later, after coach Toni Nadal had suggested a minor change to his nephew's serve, he was on his way to his third Grand Slam title of the year, serving better than he had ever done before.
The defending champion arrived here last week in arguably even worse shape than last year. Not only had he played below par in the summer's two Masters Series tournaments but he was also suffering physically. The foot injury that troubled him at Wimbledon was still a problem and he was nursing burns to his fingers suffered in a restaurant.
It remains to be seen whether the foot injury in particular will be a problem for Nadal – he said his fingers were "much better" – but the French Open champion got his tournament under way with a typically gutsy 6-3, 7-6, 7-5 victory over Kazakhstan's Andrey Golubev on Tuesday night. Nadal saved seven set points in the second set and recovered from two breaks down in the third to earn a second-round meeting with France's Nicolas Mahut.
Nadal admitted afterwards that he had felt nervous going into his first match. "I think I didn't play that bad," he said. "The mental part was positive tonight. The tennis for sure can improve. I have to play a little bit more inside the court, but I am confident I can do it."
He added: "I didn't play a lot this summer. I have had a fantastic week of practice here. I was practising really well, much better than in the previous tournaments. It's normal to start like this, with doubts, with more nerves. You have to find your confidence. Confidence comes from spending hours on court, competing better, winning matches."
Nadal said he was happy with the way he had been hitting the ball but felt that he needed to be more positive on his backhand. "Hopefully for the next match I will do it much better," he said. "People forget a lot of things, but last year my first match was really bad. That's the truth. Even if I didn't lose my serve, I played badly against a similar opponent [Teymuraz Gabashvili] to today's.
"He [Golubev] played very fast. It was a different situation, but it's very difficult to start one tournament playing very well from the beginning. I am not saying that I will play fantastic in the next days, but I am confident that I can do it better."
Novak Djokovic came through his first-round match with considerably less difficulty after his opponent, Conor Niland, retired when trailing 6-0, 5-1. Niland had been suffering from food poisoning after a meal out in what he described as a "fancy restaurant" in Manhattan on Sunday night.
It was a stroke of desperately bad luck for the first Irishman to play here in the Open era. Niland, 29, had never met an opponent ranked in the world's top 50 before and was playing in only his second Grand Slam tournament, having also qualified for Wimbledon this summer.
"For the last couple of days I've been cursing my luck," the world No 197 said after his retirement. "It's a once-in-a-lifetime kind of a match and to not be able to go out and show what I can do and be just normal and healthy out there is really frustrating. I felt like I really wanted to start in case a miracle happened and I felt good out there. I thought maybe I could bluff my way through, but I just found out you can't do that against the No 1 in the world."
After the relentless demands of his extraordinary season, Djokovic was happy to be detained on court for only 44 minutes. The world No 1, who has won nine titles this year and lost only twice, was playing his 60th match of the campaign. As a comparison, Andy Murray had played only 44 matches going into his opening match last night against India's Somdev Devvarman.
Djokovic, who reported no pain in the injured shoulder that forced him to retire from his recent Cincinnati Masters final against Murray, said: "I'm not really tired because I switched to the mode of Grand Slam focus. I'm trying to prepare well, and be 100 per cent mentally and physically fit for the matches that are about to come here.
"Today was a great opening performance. I know it has been a long year, but it's not the first time. I've played many matches in the past, as well, but you've got to adjust to it. I think right now I'm doing a quite good job to stay fit."
Robin Soderling withdrew from the tournament with illness shortly before he was due to play his first-round match against the Irishman Louk Sorensen. The world No 6 was replaced by a lucky loser, Brazil's Rogerio Dutra Da Silva.