Acapulco - Top-seeded Kei Nishikori of Japan beat fifth-seeded Alexandr Dolgopolov of Ukraine 6-4, 6-4 on Thursday to reach the Mexico Open semi-finals.
Nishikori will face fourth-seeded Kevin Anderson of South Africa, a 3-6, 6-3, 6-3 winner over Serbia's Viktor Troicki in the hard-court event at The Fairmont Acapulco Princess.
In the night quarterfinals, second-seeded David Ferrer of Spain faced Australia's Bernard Tomic, and sixth-seeded Ivo Karlovic of Croatia played Ryan Harrison of the United States.
In women's play, Bulgaria's Sesil Karatantcheva topped Monica Puig of Puerto Rico, 2-6, 7-6 (7), 6-4. Karatantcheva will play fifth-seeded Timea Bacsinszky of Switzerland, a 6-3, 6-3 winner over Johanna Larsson of Sweden.
In the other quarterfinals, top-seeded Maria Sharapova of Russia faced Magdalena Rybarikova of Slovakia, and third-seeded Caroline Garcia of France played Mirjana Lucic-Baroni of Croatia.Results on Thursday from the fourth day of the Mexican Open ATP and WTA tournament (x denotes seeded player):
Kei Nishikori (JPN x1) bt Alexandr Dolgopolov (UKR x5) 6-4, 6-4
Kevin Anderson (RSA x4) bt Viktor Troicki (SRB) 3-6, 6-3, 6-3
Maria Sharapova (RUS x1) bt Magdalena Rybarikova (SVK) 6-1, 4-6, 6-2
Caroline Garcia (FRA x3) bt Mirjana Lucic-Baroni (CRO) 6-2, 2-1 retired
Timea Bacsinszky (SUI x5) bt Johanna Larsson (SWE) 6-3, 6-3
Sesil Karatantcheva (BUL) bt Monica Puig (PUR) 2-6, 7-6 (9/7), 6-4