World number one Rafael Nadal says it is too early to compare him to Roger Federer despite becoming only the seventh man to win all four grand slam tennis tournaments.
Nadal, 24, beat Novak Djokovic in the U.S. Open final in New York on Monday to win his ninth grand slam title, moving within seven of Federer's record haul of 16.
But asked about comparison's with the Swiss, Nadal told CNN: "I think he is the best -- I am very far from him. It's difficult to say I am like Roger -- I never thought that way.
"But I am very happy with what I did. I want to keep playing how I have been playing."
Nadal produced some of the best tennis of his career to become the first man since Rod Laver in 1969 to win the French Open, Wimbledon and the U.S. Open in the same year.
He only lost one set in the entire tournament -- to Djokovic in the final -- and his serve was only broken on five occasions -- equaling a record set by Andy Roddick in 2003.
Worryingly for his opponents, Nadal has vowed to get even better.
"I want to keep working hard and keep improving and keep playing with the same motivation," he said. "That way I will keep having chances in the final rounds of tournaments.
"All my life I practiced with high-intensity. I think you play like you practice. I love competition and the sport in general so when I go on court I always try my best. I try to enjoy it and fight every moment."
While Nadal was keen to play down his achievement, Djokovic was in no doubt that he had just lost to a player capable of becoming the greatest in the history of the sport.
"He's so mentally strong and dedicated to this sport," the Serbian third seed, who beat Federer in the semifinals, told reporters. "He has all the capabilities, everything he needs, in order to be the biggest ever.
"He has the game now for each surface and he has won each major. He has proven to the world that he's the best in this moment, so there is no question about it."