Top-seeded David Ferrer of Spain easily defeated Fernando Gonzalez of Chile 6-2, 6-4 on Friday to advance to the semifinals of the Copa Claro clay-court tournament.
Ferrer's semifinal opponent on Saturday will be David Nalbandian, who defeated fellow Argentine Carlos Berlocq 6-0, 6-3.
Defending champion and second-seeded Nicolas Almagro of Spain also reached the final four with a 6-3, 7-5 victory over Igor Andreev of Russia.
Almagro will next meet No. 6 Stanislas Wawrinka of Switzerland, who defeated No. 4 Kei Nishikori of Japan 6-4, 6-2.
Ferrer broke Gonzalez in the ninth game of the second set, and then served out to win the match. The loss eliminated Gonzalez, who has only one more tournament to play - next month's Masters in Florida - before he retires.
"It was a difficult match," Ferrer said. "Fernando is a great player, one of the greatest in history. And as a person he is even better."
Gonzalez, 31, reflected on his penultimate tournament before retiring after several injury-plagued seasons.
"The last tournament," Gonzalez said, pausing to reflect on the words. "I'm glad I'll have time to recover after all the running that David made me do."
Almagro is trying to win back-to-back events after taking the Brazil Open last week.
"I'm happy after having beaten a great player like Igor," Almagro said. "The second set was very tough."