Roddick outlasts Querrey to reach Memphis semis

MEMPHIS, Tennessee (Reuters) - Top-seeded American Andy Roddick outslugged compatriot Sam Querrey 6-4 3-6 6-3 to advance to the semi-finals of the Memphis Championships on Friday.

In a battle between two booming servers, Roddick was broken just once while his opponent dropped serve four times, which proved to be the difference.

Roddick, attempting to improve on his run to the semi-finals at last week''s San Jose Open, got off to a strong start in winning all but six points on serve in a dominant first set.

The 21-year-old Querrey responded with eight of his 15 total aces in the second to seize the momentum but his main weapon deserted him in the decider, with his first serve percentage dropping to 50, allowing Roddick to close out the match.

Roddick now awaits the winner of the late match between Lleyton Hewitt and Belgian Christophe Rochus.

In other action, Radek Stepanek advanced to the last four with a 7-6 6-4 victory over Argentine second seed Juan Martin del Potro.

The in-form Czech is gunning for his second consecutive title, having won in San Jose last week, and his next opponent will be Dudi Sela, who outlasted Igor Kunitsyn 4-6 6-4 6-2.

The top two players advanced to the final of the women''s event, with top seeded Dane Caroline Wozniacki easing past Briton Anne Keothavong 6-1 6-0 and number two Victoria Azarenka of Belarus battling to a 6-4 3-6 7-6 victory over Sabine Lisicki.

(Writing by Jahmal Corner in Los Angeles; Editing by John O''Brien)