WINSTON-SALEM, North Carolina, Aug 23, AFP – Czech second seed Tomas Berdych and US seventh seed Sam Querrey advanced to a semi-final matchup at the ATP Winston-Salem Open with three-set victories on Thursday.

Berdych ousted Belgian Steve Darcis 4-6 6-2 6-0 while Querrey outlasted Ukraine fourth seed Alexandr Dolgopolov 7-5 4-6 7-6, firing 20 aces in the match to win after two hours and 11 minutes.

Berdych is the sixth seed at the US Open and will begin play next week in the year’s final Grand Slam tournament against Belgian David Goffin.

Querrey, seeded 27th at Flushing Meadows, will open against Taiwan’s Lu Yen-Hsun next week and could see Berdych in the third round.

Dolgopolov, the US Open’s 14th seed, will open against American Jesse Levine and could face defending US Open champion Novak Djokovic in the round of 16.

French top seed Jo-Wilfried Tsonga was to face Spanish sixth seed Marcel Granollers and US third seed John Isner was to meet Goffin in later quarter-final matches.