NEW YORK (AP) - In the second official match he ever played, Novak Djokovic faced Viktor Troicki in the under-10 division.

"He destroyed me," Djokovic recalled Tuesday.

The scene was being repeated about 15 years later in the first round of the U.S. Open.

"Today he was the better player on the court - for a while," the third-seeded Djokovic said of his friend from Serbia.

Djokovic, a year younger but now ranked 44 spots higher, rallied in the searing heat for a 6-3, 3-6, 2-6, 7-5, 6-3 win.

Down two sets to one, Djokovic had his serve broken in the first game of the fourth set. Troicki nearly went up two breaks, but the 2008 Australian Open champ fought off break points in his next two service games.

"He knew that I might go down a little bit after that chance, so for sure he was more pumped," Troicki said. "He knew that was maybe the last moments to try to play better and stay alive."

Troicki had 23 aces. In winning the second and third sets, he hit 71 percent of his serves in - and won 87 percent of those points.

"I never saw him serve that way," Djokovic said.

He should know, since the two practiced together for years.

But Djokovic started picking up Troicki's serve better in the final two sets and outlasted the sun.

"You just have to try to be patient and wait for the shadows," he said, "like I did."