World number one Serena Williams swept past good friend Caroline Wozniacki of Denmark 6-3,6-3 in the US Open final to win her 18th grand slam title.

Her win on Sunday was the third straight and sixth overall US Open crown for the American, who has failed to get beyond the last 16 of the last three grand slam tournaments this year.

Williams sailed through the tournament without dropping a set, finishing off Wozniacki in a snappy 75 minutes.

"It was a pleasure for me to win my first grand slam here, and then this is number 18."

Serena Williams,

"It was a pleasure for me to win my first grand slam here, and then this is number 18. I am really emotional," Williams told the packed Arthur Ashe Stadium.

Wozniacki, the 10th seed, was in her first grand slam final in five years.

Williams pocketed the $3m winner's purse along a $1m bonus for winning the US series.

The most difficult part of the match for Williams appeared to be beating a player she calls one of her best friends.

Williams and Wozniacki holidayed together this summer and the world number one said she texts the Dane daily.

But once the match began, Williams, who has often had to face off against her sister Venus, again proved there are no friendships on the court as she simply overpowered her 24-year-old opponent.

The showdown between the current and former world number ones was hardly a showcase of tennis excellence, particularly in a ragged opening set that featured five consecutive breaks.

Williams held her first serve before the two players struggled through the run of breaks with the American taking a 5-2 lead.

Not until the eight game did Wozniacki finally held serve but by then Williams had begun to settle into the match, clinching the opening set with a blistering backhand winner.

Williams would keep up the pressure with a break to open the second.

Source: Agencies