NEW YORK - Top-seeded Novak Djokovic defeated world No 99 Jenson Brooksby of the United States 1-6, 6-3, 6-2, 6-2 in the fourth round of the US Open men's singles on Monday.

In face of the 20-time major singles champion Djokovic, the young American challenger showed his confidence and won the first set by an obvious advantage.

"Jenson was pumped, he had a clear game plan, he was executing all the shots very efficiently, and I was really on my back foot," Djokovic said of his slow start. "I didn't have the rhythm, made a lot of unforced errors and he was reading the play very well for about a set and a half."

However, the world No 1 quickly recovered and won the following three straight sets.

"He is a very young, very talented player, I told him at the net that a very bright future is ahead of him. Definitely, he's a great player," Djokovic added after the victory.