Houston - Top seed Nicolas Almagro capitalized on all three break point chances as he beat seventh seed Paolo Lorenzi in straight sets to reach the semi-finals of the US Clay Court Championships.
Almagro, who has won all 12 of his ATP Tour titles on clay, rolled over the Italian 6-4, 6-4 in their centre court match Friday at the River Oaks Country Club.
The 27-year-old Spaniard Almagro blasted nine aces, had one double fault and won 75 percent of his first-serve points in the $455,775 clay court tournament.
Lorenzi hammered five aces and had three double faults in the 81-minute centre court match.
Almagro next faces American wild card Rhyne Williams, who reached his first-ever ATP semi-final by outlasting Spain's Ruben Ramirez Hidalgo 7-6 (7/1), 1-6, 6-4 in just under two and a half hours.
The 22-year-old Williams finished with five aces and won 58 percent of his second-serve points compared to just 39 percent for the Spaniard.
American John Isner reached the semis with a 6-3, 3-6, 6-3 win over Ricardas Berankis, who beat second seed Tommy Haas in the previous round.
The fifth-seeded Isner blasted 19 aces and won 89 per cent of his first serve points to advance past the Lithuania's Berankis in 83 minutes.
Results on Friday from the fifth day of the $455 775 ATP US Clay Court Championships (x denotes seeding):
Nicolas Almagro (ESP x1) bt Paolo Lorenzi (ITA x7) 6-4, 6-4
Rhyne Williams (USA) bt Ruben Ramirez Hidalgo (ESP) 7-6 (7/1), 1-6, 6-4
John Isner (USA x5) bt Ricardas Berankis (LTU) 6-3, 3-6, 6-3