Clijsters, unseeded in the wake of a lengthy injury layoff, needed just 62 minutes to end Mauresmo's hopes of a first title at Key Biscayne.

She also ended the French player's chance of regaining the world number one ranking from American Lindsay Davenport at this event.

Mauresmo would have needed to beat second-seeded Wimbledon champion Maria Sharapova in the final to unseat Davenport.

Instead, 17-year-old Sharapova, who beat American Venus Williams 6-4, 6-3 in the semifinals, can claim the world number two spot from Mauresmo if she beats Clijsters in Saturday's final.

Mauresmo had four break points against Clijsters in the opening set and failed to convert all of them. After that, she said, there was little she could do.

Sharapova made sure that for the first time since 2000 - when Martina Hingis won - a Williams won't lift the women's trophy at Key Biscayne.

Venus Williams won the last of her three titles here in 2001, and Serena Williams launched her run of three straight in 2002.

Venus ended Serena's run with a quarter-final win over her sister on Tuesday. But the eighth-seeded American never looked as if she would get past Sharapova.

Williams's only break opportunities came in the final game of the match, but it proved too little too late as she failed to capitalize on any of her six chances to keep the contest going.

The match-ups for Friday's men's semi-finals were completed as world number one Roger Federer, seeking a first Key Biscayne crown, lined up a clash with six-time Miami champion Andre Agassi.

Switzerland's Federer dispatched sixth-seeded Briton Tim Henman 6-4, 6-2. Agassi, seeded ninth, downed fellow American Taylor Dent 7-5, 6-0.

Henman, one of the few players still boasting a winning record against Federer, couldn't improve on that.

He said he didn't play badly, but against Federer these days, that's just not enough.