Third-seeded Amelie Mauresmo of France and No 4 Elena Dementieva of Russia booked a final clash in the 585,000-dollar WTA indoor tournament here on Saturday.
Dementieva didn't even have to lift a racquet, moving into the final in a walkover when sixth-seeded compatriot Nadia Petrova was sidelined by injury.
Petrova suffered a right heel bruise in a quarter-final triumph over Slovakian Martina Sucha.
"I am very disappointed that I can't play today," Petrova said in a statement. "I was looking forward to my semi-final match and have always enjoyed playing in the Advanta Championships."
The unscheduled rest-day might have come as a relief for Dementieva, who needed to rally for a 4-6, 6-0, 6-3 victory over Kveta Peschke of the Czech Republic on Friday.
With that victory she secured the final spot in next week's WTA Tour Championships in Los Angeles.
Before turning her attention to the season finale, however, Dementieva will have a chance to stop Mauresmo's winning streak in Philadelphia.
The Frenchwoman is the two-time defending champion here and snapped seventh-seeded Czech Nicole Vaidisova's 18-match winning streak 7-5, 7-5 to reach another Philadelphia final.