Pierce, who suffered severe cramp in the closing games of her singles semifinal victory over Martina Hingis on Thursday, showed no after-effects in the 2-6 6-2 6-1 victory over France's Nathalie Tauziat and Barbara Fusai.
She hit the ball strongly and served well.
Pierce and Hingis, the third seeds, meet 10th seeds Virginia Ruano Pascual of Spain and Argentina's Paola Suarez in the final on Sunday.