World No 1 Novak Djokovic has vowed to bounce back from his four-set loss to Rafael Nadal in the US Open final.
Djokovic went down 6-2 3-6 6-4 6-1 to Nadal - with the 26-year-old having now fallen at the final at hurdle at Flushing Meadows for the third time in four years.
However Djokovic is determined to use the defeat as his motivation moving forward.
"I have to use it. It's part of my life," Djokovic said. "Many times you fall as an athlete and you have to learn the lesson and keep on going, keep on fighting, keep on improving. That's what we are here for.
"I'm still 26 and I believe the best time for my career is about to come. I feel that. As long as I believe it, the fire of the love toward the game is inside of me.
"And as long as that's present, as long as I feel it, I'm going to play this sport with all my heart, as I did in the last 10 years."
Djokovic was his own worst enemy as he committed 53 unforced errors, allowing Nadal to take control.
"It's all my fault," he said. "I made some unforced errors in the crucial moments with forehands and dropped the serve twice when I should not have.
"All of a sudden it's two sets to one for him. Then he started playing much better after that and I obviously could not recover.
"In the important moments he played better tennis and that's why he deserved to win. I was supposed to use the opportunities that were presented to me and I didn't do it. I didn't deserve to win in the end.
"I was playing well throughout the whole two weeks, and I can be happy because it was different from the hard-court tournaments prior to the US Open. I felt more mentally present and I was going for my shots."
Djokovic also praised Nadal, adding: "Well, 13 grand slams for a guy who is 27 years old is incredible.
"What he achieved so far in his career is something that everybody should respect, no question about it. He's definitely one of the best tennis players ever."