Twelfth seed Mary Pierce rallied to beat Russian sixth seed Elena Dementieva 3-6 6-2 6-2 to become the first Frenchwoman to reach the US Open final.
Dementieva, runner-up last year, ripped through the first set but Pierce lifted her game after a 12-minute injury timeout to clinch victory and set up a final against Russian top seed Maria Sharapova or Belgian fourth seed Kim Clijsters.