Fourth seed Elena Dementieva of Russia [Images] rallied for a 4-6, 6-0, 6-3 quarter-final win over the Czech Republic's Kveta Peschke at the Advanta Championships in Philadelphia on Friday, securing the eighth and final berth in the WTA's Tour Championships.

Dementieva's victory denied American Venus Williams [Images] a spot in the $3 million season finale beginning next week in Los Angeles.

Already qualifying for the tournament were Kim Clijsters [Images], Lindsay Davenport [Images], Maria Sharapova [Images], Mary Pierce, Amelie Mauresmo, Patty Schnyder and Nadia Petrova.

Dementieva held a 2-1 edge in head-to-head meetings going into the pivotal match but Peschke had won their only meeting in the last four years with a quarter-final victory over the Russian in Linz.

Third-seeded Mauresmo moved a step closer to capturing her third straight Advanta title, easing into the last four with a 6-3, 6-4 win over American Mashona Washington.

The Frenchwoman will next meet Czech teenager Nicole Vaidisova who swept into the semi-finals by dismissing Lisa Raymond of the United States 6-4, 6-1.

The other semi-final will be an all-Russian showdown with Dementieva taking on sixth-seeded compatriot Nadia Petrova who battled past Slovakia's Martina Sucha 7-5, 7-6 (7-5) to reach the final four for the third time.

It was the seventh consecutive win for Petrova who has carried her form over from her first career title in Linz last week.

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