Alexandr Dolgopolov cut the knuckle on his left thumb, forcing him to take an injury timeout.
Streeter Lecka/Getty Images

WINSTON-SALEM, N.C. (AP) -- Alexandr Dolgopolov of the Ukraine overcame a knuckle injury on his left hand to beat Lu Yen-Hsun of Taiwan 7-6 (7) 6-3 on Thursday in the quarterfinals of the Winston-Salem Open.

Dolgopolov, No. 38 in the world, advanced to a tournament semifinal for the first time this season, and will play France's Gael Monfils Friday at the Wake Forest Tennis Center. Monfils advanced by beating Spain's Fernando Verdasco 6-7 (10) 6-4 6-4.

The right-handed Dolgopolov had to take an injury timeout in the fifth game of the second set after hitting his left thumb with the frame of his racket on a forehand shot.

"I couldn't feel it much for a few games,'' Dolgopolov said. "It just aches - not a hard pain, but it threw off my concentration a bit. Stuff like that happens. You have to deal with it and get back as fast as you can.''

Dolgopolov, who had a half-inch cut on the first knuckle of his left thumb, lost serve in that game. But he broke right back in the sixth game, then registered another service break two games later.

"I wasn't happy I lost the break,'' said Dolgopolov, who had nine aces against No. 62 Lu. "I was serving pretty solid all match, but after that, I gave away three points that he didn't do much to break. After that, I did pretty well for a few games.''

Monfils, ranked No. 7 in 2011 only to see that slide because of injuries, had key service breaks in the second and third sets to move into a tournament semifinal round for the fifth time this season.

"It's always good to be in the semifinals, especially after two big wins,'' said Monfils, who had seven aces and just one double fault. "He's very aggressive, hitting lots of winners and making lots of mistakes. It makes you play a bit different.''

In other quarterfinal matches scheduled Thursday, Russian Dmitry Tursunov faces Austria's Jurgen Melzer in an afternoon match, and American Sam Querrey - at No. 29, the highest ranked player remaining in the field - will play Ricardas Berankis of Lithuania.

Copyright 2014 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

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