Serena Williams claimed her third US Open women's title with a 6-4, 7-5 victory over Jelena Jankovic at Flushing Meadows.

Despite making 39 unforced errors, the fourth seed prevailed in just over two hours against the second seeded Serbian, who has yet to win a grand-slam title.

"I am so excited," Williams said. "Usually after a grand slam I feel like I still have another match to play but I don't really feel that way today. I feel like it's done and it's all over and I am so excited. I just think it showed on the court."

Williams, who won the US Open in 2002 and 1999, is enjoying a renaissance season on the WTA Tour with four titles, taking her career total to 32 and she plans to add to her grand slam collection. "It doesn't stop here," she said. "I feel so young and so energized every week. It feels like I am having a new career."

Williams struggled with unforced errors early on, dropping her second service game of the match to love and she looked set to go 3-1 down when Jankovic went 40-0 up in the next game. But she battled back, winning the next five points to break the Serbian and claimed another break on Jankovic's next service game as she moved into a 5-2 lead.

Serving for the set at 5-3, Williams put herself into a 0-40 hole and surrendered the game after saving two break points. But she had Jankovic in the same position in the next game and claimed the opening set 6-4 when the Serb put her return on the second set point long.

Jankovic appeared out of sorts at the start of the second set and faced two break points in her first service game before holding for 1-1. After five breaks of service in the opening set, the first six games of the second set went according to serve until Williams put a lazy drop shot from the baseline into the net to give Jankovic a 4-3 advantage.

The Serbian had a chance to close out the set when she went 40-0 up in Williams' next service game but the American held and broke Jankovic in the next game to make it 5-5. Williams held to make it 6-5 and then took the match by breaking Jankovic with her 44th winner of the match.

Jankovic, who was competing in her first grand slam final, said she squandered her chances on the big points. "I am disappointed that I lost," she said. "It is not pleasing when you lose. I felt I had her because she was really tired at the end of the second set.

"I gave everything. I had had my chances in the first set and second set. I had some unlucky points I should have won them and I didn't.

"Serena played better tonight. She was too good."

This is the ninth time in history that a grand-slam final has featured two women battling for No 1 in the world. Williams surpasses former No 1 ranked player, Ana Ivanovic, who reigned for 12 weeks before being knocked out in the second round of the final major championship of the season.