ATP: Jack Sock avoids upset, advances to the Houston semi-finals

New Delhi: High seeds John Isner and Sam Querrey were sent packing in three sets, while No. 1 seed Jack Sock survived a scare at the ATP Tour`s Houston event Friday.

Second-seeded Isner was ousted by fellow American Ernesto Escobedo 7-6 (8/6), 6-7 (6/8), 7-6 (7/5) and third-seeded Querrey lost 6-4, 3-6, 6-3 to Brazilian eight-seeded Thomaz Bellucci in the quarter-finals.

Sock avoided an upset, advancing to the semi-finals with a 7-6 (8/6), 1-6, 6-4 victory over Feliciano Lopez of Spain.

The 20-year-old Escobedo beat former tournament winner Isner despite posting just 10 aces to his opponent`s 35.

Fourth seed Steve Johnson eased through to the semis with a 6-2, 6-4 victory over Spanish fifth seed Fernando Verdasco.

Escobedo, who is ranked No. 91 in the world, will face Bellucci in the semi-finals.

Escobedo is competing in his first clay-court tournament and just his ninth ATP Tour event overall.

"I can`t believe it," Escobedo said. "To do it here in Houston, it`s amazing.

"(It`s) such a relief. Past years I`ve been training so hard and now it`s paying off."