WASHINGTON — Marin Cilic and Kei Nishikori will meet in the semifinals at the Citi Open Saturday, their first encounter since the final of last year's US Open. The other semifinal will see American John Isner meet compatriot Steve Johnson after eighth-seed Isner defeated Ricardas Berankis of Lithuania 6-3, 5-7, 6-3, while Johnson upset 15th-seed Jack Sock 7-6, 6-1. Third-seed Cilic beat German teenager Alexander Zverev 7-5, 7-6 in quarterfinal action Friday, while second-seed Nishikori ended the run of Australian qualifier Sam Groth 6-4, 6-4. Japan's Nishikori has beaten Cilic in five of their eight head-to-head matches, but in their last meeting at Flushing Meadows last September the Croatian prevailed in straight sets (6-3, 6-3, 6-3) to win his first Grand Slam title. Nishikori has been one of the strongest players this season. He has moved up to No. 5 in the world rankings with a 41-9 record. Only Novak Djokovic (48-3) and Andy Murray (48-8) have more match wins on the 2015 ATP World Tour. “Hopefully, I can get some revenge against Marin,” Nishikori said. “I've been playing good here and hopefully I can come up with another good one in the semis tomorrow.” In the women's quarterfinals, 2011 US Open champion Sam Stosur advanced when Monica Niculescu stopped playing because of a left abdominal strain while trailing 4-0. “It seemed like straightaway, something wasn't right with her,” said Stosur, adding that while she never wants to take advantage of an opponent's injury, she was “not going to complain” about spending less than a half-hour on court. Stosur faces Sloane Stephens Saturday. Stephens picked up a 6-4, 6-4 victory over 19-year-old wild-card entry Louisa Chirico. The other women's semifinal will be No. 1-seeded Ekaterina Makarova against Anastasia Pavlyuchenkova. Marakova beat No. 6 Irina-Camelia Begu 6-4, 2-6, 6-1, while Pavlyuchenkova edged Christina McHale 2-6, 6-1, 7-6 (5). Kohlschreiber wins in Kitzbuehel Philipp Kohlschreiber won his sixth career ATP title by rallying to defeat French qualifier Paul-Henri Mathieu 2-6, 6-2, 6-2 at the Generali Open Saturday. It was the first title in 15 months for the sixth-seeded German, who improved to 6-7 in finals. Coming back from injuries, the 109th-ranked Mathieu was looking for his first title in eight years and fifth overall. He hasn't beaten Kohlschreiber since 2003. The Generali Open was the final clay-court tournament of the season. In the semifinals, Kohlschreiber defeated top-seeded Dominic Thiem 6-0, 7-6 (6) and Mathieu beat Nicolas Almagro of Spain 6-4, 6-3, Pliskova reaches semis Karolina Pliskova of the Czech Republic advanced to the Bank of the West Classic semifinals Friday, beating Croatia's Ajla Tomljanovic 6-2, 6-4. The 11th-ranked Pliskova will make her debut in the top 10 when the new rankings are released Monday. Only world No. 1 Serena Williams, who withdrew from Stanford with an elbow injury, has more wins (40-1) than Pliskova (38-14) this year and the fourth-seeded Czech player snapped a tie with Williams for most aces on the tour. Pliskova has 361 to Serena's 352. On Saturday, Pliskova will face Varvara Lepchenko of the United States. The 60th-ranked beat Mona Barthel of Germany 6-7 (3), 6-2, 6-3. Pliskova will become the eighth Czech woman to be ranked in the top 10 since the current system was introduced in 1975, and three Czech women will be among the top 10 for the first time in WTA history. Ukraine's Elina Svitolina advanced with a 4-6, 7-5, 6-1 victory over American Alison Riske. Svitolina will play No. 14 Angelique Kerber of Germany, a 4-6, 6-4, 6-4 winner over No. 7 Agnieszka Radwanska of Poland. — Agencies
