Results in the Birmingham WTA tournament on Saturday (x denotes seeding:: Quarter-finals Coco Vandeweghe (USA) bt Marie Bouzkova (CZE x8) 6-4, 6-4 Daria Kasatkina (RUS x4) bt Tereza Martincova (CZE) 6-4, 2-6, 6-0 Heather Watson (GBR) bt Donna Vekic (CRO x3) 6-4, 6-2 Ons Jabeur (TUN x2) bt Anastasia Potapova (RUS) 6-4, 6-0 Semi-finals Daria Kasatkina (RUS x4) bt Coco Vandeweghe (USA) 6-2, 6-4 Ons Jabeur (TUN x2) bt Heather Watson (GBR) 6-3, 6-3 afp