Roger Federer looked good all-tournament long and was tipped to win his 18th Grand Slam title, but Novak Djokovic was also determined to add another feather in his cap.

Djokovic scored a hard-earned 6-4, 5-7, 6-4, 6-4 victory over Federer in the 2015 US Open tennis final on Sunday night at Arthur Ashe Stadium in New York.

Djokovic, the top-seeded player in the men's draw, had the first break of the match, but he looked rattled after suffering a bad fall during the opening set. Federer quickly took advantage and won two straight games, but the top-seeded Serb managed to regroup and win the first set.

Federer displayed flashes of brilliance in the second set as he stood toe-to-toe with Djokovic to tie the game at 1-1. However, Djokovic took control again in the third set and did not let Federer get into his rhythm again en route to the win at Flushing Meadows.

Djokovic admitted that he felt a lot of pressure during the fourth set, especially when he was serving for the match. He knows he was going against arguably the best tennis player in history, and his opponent is capable of launching a huge comeback.

"I was serving at 5-2 in the fourth set and Roger showed why he's a champion," Djokovic said via ESPN. "I was forced to come up with some big serves. Obviously, it was a big relief when I saw the forehand return going out."

With the win, Djokovic has racked up 10 Grand Slam titles, including two at Flushing Meadows. The 28-year-old Serb won three Grand Slams this year. He failed to win the French Open title, but also played in the final against eventual winner Stan Wawrinka of Switzerland.

"It's been an incredible season, next to the 2011 season, the best of my life," Djokovic said. "I'm enjoying it more as a husband and a father, and this makes it sweeter. It's a quite incredible evening for me."

Federer accepted the defeat, admitting that Djokovic played better than him. He also pointed out that he had several chances in the match, but he failed to capitalize. The second-seeded Swiss had 23 break points, but only won four.

"I had too many break chances," Federer said in a post-match interview. "Of course some of them I could have done better, should have done better, you know, all these things. Surely he didn't give me much, you know, and all that, that's for sure, but still I should have done better."

Highlights of the Djokovic-Federer 2015 US Open Final match can be seen on this link.