Nicolas Almagro will play American Rhyne Williams in the semifinals in Houston.
Pat Sullivan/AP

Top-seeded Nicolas Almagro of Spain advanced to the U.S. Men's Clay Court semifinals Friday, using service breaks at the end of each set to beat Italy's Paolo Lorenzo 6-4, 6-4.

Almagro, ranked 12th in the world, will face Rhyne Williams, the American wild card who rallied from an 0-3 deficit in the third set to beat Spain's Ruben Ramirez Hidalgo.

In the other semifinals, third-seeded Juan Monaco of Argentina faced American Robby Ginepri, and fifth-seeded John Isner of the United States was set to play Lithuania's Ricardas Berankis.

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