New York: Rafael Nadal`s impressive return from a seven-month injury layoff, with a haul of nine titles including a French Open and an unbeaten 15-match hardcourt run, has made him a marked man at the US Open.
"Nadal is definitely back and he`s playing maybe the best tennis that he ever has played on hard courts," said world number one Novak Djokovic.
"He`s definitely so far the best player this year. There is no question about it. The results are showing everything."
After healing the nagging knee injuries that have bothered him for years, Nadal dominated on his beloved clay with wins at Sao Paulo, Acapulco, Madrid, Rome, Barcelona and Roland Garros for his 12th career Grand Slam crown and eighth French Open title in nine years.
But what impresses his rivals on the Flushing Meadows hardcourts, where the year`s final Grand Slam event starts Monday, is his unbeaten run on hard courts, taking titles at Indian Wells and in August at Montreal and Cincinnati in his US Open tuneups.
"He has beaten some tough players in tough tournaments," defending US Open champion Andy Murray said.
"It`s not like he`s had easy draws or whatever. He`s beaten some top, top players. Yeah, he`s going to be very difficult to beat here."
Nadal, for his part, plays down the performance.
"I had a great summer, but that`s all. Doesn`t mean nothing else," Nadal said. "I hope to be very competitive for the first match."
Djokovic sees a more attacking Nadal adapting to the hardcourts to help ease the stress on his knees.
"He seems like he changed a little bit," Djokovic said. "He stepped in a little bit more. He knows that now he has to be a bit more aggressive than he usually is because of, I guess, his knees and everything and because hard court is not clay. It`s not his favorite surface. It`s faster.
"I`m sure he worked on that and you could see that all the work he put in is getting results."
And 17-time Grand Slam champion Roger Federer, who could face Nadal for the first time at a US Open in the quarter-finals, has been dazzled by Nadal`s performance.
"I`m very impressed, especially seeing him play really well on the quicker hard courts," Federer said.
"He is someone to be reckoned with.”
"He has had an incredible season so far. So, I mean, it`s super impressive and I hope for him he can keep it up."
Nadal does not give all the credit to a change in game plan on hardcourts.
"I think you can play aggressive when you`re playing well," he said. "I am trying to take the ball a little bit early. I worked on my game to be a little bit more aggressive.
"But at the same time, it is true that in the past when I was playing well on this surface I had good success, too. So it`s not something crazy that changed.
"I am confident for here. It`s great because I won two very important tournaments. Here is a different event. I`m going to keep trying my best and I hope to be ready."
Nadal did sound a warning for the ATP that hardcourts would shorten the careers of the game`s top stars.
"For the future generations it would be better if the ATP can find a solution because the hard court is still a little bit too aggressive to have a very long career," Nadal said.
Nadal, Murray and Djokovic each seek a second Slam title this season and a leg up in year-end world number one honors.
"If I am number one, it will be amazing, amazing season for me," Nadal said. "If I am not number one, it still will be amazing season for me. This tournament is going to make a big difference."