Defending champion Serena Williams and Maria Sharapova booked quarter-final berths at the Cincinnati Masters on Thursday.
World No.1 Williams dismantled Italian 13th seed Flavia Pennetta 6-2 6-2 while fifth seed Sharapova beat Anastasia Pavlyuchenkova 6-4 7-6 (7-2).
Williams next plays eighth seed Jelena Jankovic, who beat Sloane Stephens 7-6 (7-4) 6-4.
Also through was world No.2 and second seed Simona Halep, a 6-4 7-5 winner against Czech Lucie Safarova.
“Today was much better than my first match here,” said Halep, winner in Bucharest last month and runner-up to Maria Sharapova at Roland Garros.
“I was happy to win in two sets, since she was up 5-4.”
Halep earned a mouth-watering rematch with fifth-seeded Sharapova, who beat fellow Russian Anastasia Pavlyuchenkova 6-4 7-6 (7-2).
Sharapova had to rally from a break down three times in the second set but managed to finish it off in two.
Ukrainian teenager Elina Svitolina, who took out double Wimbledon winner Petra Kvitova in the second round, claimed her second seeded victim with a defeat of Spain’s world No.16 Carla Suarez Navarro 4-6 6-4 6-4.
She’ll next face former world No.1 Ana Ivanovic, a 6-2 2-6 6-3 winner over Svetlana Kuznetsova.
Fourth-seeded Agnieszka Radwanska of Poland cruised past Germany’s Sabine Lisicki 6-1 6-1 and will take on Denmark’s Caroline Wozniacki, a 7-5, 6-2 winner over sixth-seeded German Angelique Kerber.