WINSTON-SALEM — Second-seeded Kevin Anderson of South Africa beat eighth-seeded Borna Coric of Croatia 6-2, 7-6 (1) on Thursday night to advance to the semifinals in the Winston-Salem Open. Anderson, ranked 15th, will face 88th-ranked Malek Jaziri of Tunisia, a 6-3, 6-2 winner over sixth-seeded Thomaz Bellucci of Brazil. Anderson had 10 aces Thursday in improving to 6-0 this season in quarterfinal matches, broke the 18-year-old Coric's serve twice and converted 85 percent of his first serves in winning the first set. “I really played well today, especially in that first set,” Anderson said. “It was one of those sets where everything was coming off my racket nicely, I was taking care of my service games and putting myself in each return game. When I'm able to do that, I play my best and make it as tough as possible for my opponent.” The two were even on serve in the second set to force the tiebreaker, but Coric misplayed a volley at the net with the score tied 1-1, giving Anderson the lead and beginning a run of six consecutive points to close out the match. “It was a bit of a tricky shot,” Anderson said. “Out of 100 times, you're going to maybe win that once. I got a little bit lucky on that point, but it went from 2-1 suddenly to 4-1. That gave me a bit more of confidence. Obviously, you never know what's going to happen, but as things turned out, it was in my favor going up that early.” American Steve Johnson advanced when Taiwan's Yen-Hsun Lu withdrew because of a back injury. Johnson, seeded 13th and ranked 49th, will play French qualifier Pierre-Hugues Herbert. Lu was hurt late in the third set Wednesday in his 7-6 (1), 1-6, 7-5 victory over South Korea's Hyeon Chung. He was treated after the match and Thursday morning, but the pain and cramping persisted during practice. “There's a disk that had some inflammation inside, and the inflammation got into the muscle and got it tight,” Lu said. Herbert, ranked 140th, beat Pablo Carreno Busta of Spain 4-6, 7-6 (5), 6-2 to reach his first semifinal. Wozniacki-Kvitova semis Four-time champion Caroline Wozniacki and two-time defending champ Petra Kvitova Thursday set up a mouthwatering semifinal showdown at the US Open tune-up event at New Haven. Kvitova, the second seed, rallied from 5-3 down in the opening set to beat seventh-seeded Agnieszka Radwanska of Poland 7-5, 6-4. Denmark's Wozniacki, seeded third, overcame an early break of serve, winning 11 of the next 13 games in an emphatic 6-3, 6-0 victory over France's Caroline Garcia. Wozniacki, who has been troubled by back and calf injuries this season, did much of her damage with an unexpected barrage of forehand winners. The convincing victory was a welcome respite after the 2014 US Open runner-up had to save three match points in a second-round win over Italian qualifier Roberta Vinci. But Wozniacki will face a stiff test in the semi-finals against Kvitova, as both seek a morale-boosting win ahead of the final Grand Slam of the season, which starts on Monday at Flushing Meadows. Lucky loser Lesia Tsurenko continued to make the most of her good fortune, booking a semi-final berth with a 6-2, 6-2 victory over fifth-seeded Czech Karolina Pliskova. Ukraine's Tsurenko gained a place in the draw — and a first-round bye — when top-seeded Romanian Simona Halep withdrew from the tournament. She has since defeated Czech Barbora Strycova and Pliskova, and will try to see off another Czech when she next faces fourth-seeded Lucie Safarova, a 6-7 (4/7), 6-4, 7-5 winner over Slovakia's Dominika Cibulkova. — Agencies