World number three Maria Sharapova has beaten Caroline Wozniacki to reach the semi-final of the Madrid Masters, while Serena Williams also progressed.
Sharapova, 28, won 6-1 3-6 6-3 after a tough battle with Dane Wozniacki, 24, on the clay in the Spanish capital.
World number one Williams overpowered Spaniard Carla Suarez Navarro, 26, 6-1 6-3 in her quarter-final on Thursday.
And Sharapova could face Williams, 33, in the final, who she has not beaten for nearly 11 years.
The American was too powerful for her Spanish opponent despite a fightback in the second set, in which Williams slammed her racquet into the clay after failing to close out a game to go 5-3 up.
Russian Sharapova, who won the event last year, will face compatriot Svetlana Kuznetsova, who battled back from a set down to beat Lucie Safarova of the Czech Republic 5-7 7-6 (7-5) 7-6 (7-3).
Williams plays Czech Petra Kvitova, who beat Romania's Irina-Camelia Begu 7-5 6-3.