Federer uncharacteristically lost his cool with the umpire at one point, while Del Potro remained calm under pressure to lift his first Grand Slam title.

The marathon of a match, just over four hours long, ended 3-6, 7-6, 4-6, 7-6, 6-2 to Del Potro.

“My dream is done. It’s over. I will go home with a trophy, and it's my best sensation ever in my life,” Del Potro told the tournament’s official website. “I didn't have the experiences in these types of matches. Last night was terrible. I couldn’t sleep. I was playing the best player ever in such a big stadium and in a Grand Slam final, and it weighed heavily on me. But I knew I had to keep fighting because it was a Grand Slam final, and the crowd was supporting me so much that they deserved it. They lifted me, and finally I was able to turn it around mentally. It was an amazing match, amazing people. Everything is perfect.”

Despite the loss, which denied him a sixth straight US Open title, Roger Federer didn’t look upset either.

“Five was great, four was great, too,” said Federer, who won Roland Garros and Wimbledon this year, but fell in Australia and New York. “Six would have been a dream, too. Can't have them all. I've had an amazing summer and a great run. I'm not too disappointed just because I thought I played another wonderful tournament. I had chances today to win, but couldn't take them. It was unfortunate. I thought he hung in there and gave himself chances and, in the end, was the better man,” the Swiss player said.