Ferrer recovered from 4-1 down in the first set and will next face Roger Federer who eased past Korea's Hyung-Taik Lee 6-4 6-3 to reach the quarter-finals for the third year in a row.
Federer faces 10th seed Tim Henman in Sunday's final after the former British number one beat South Korea's Lee Hyung-taik 6-4 7-6 in the other semifinal.