Romanian second seed Simona Halep recorded her first victory in eight attempts over Maria Sharapova to reach the China Open quarter-finals. World number two Halep needed just 72 minutes to beat Sharapova 6-2 6-2. She broke Sharapova five times and made only six unforced errors as her Russian opponent struggled for rhythm. Halep will next play Russia's Daria Kasatkina, who beat defending champion Agnieszka Radwanska 4-6 7-5 6-2 in two hours and 32 minutes. Both players used drop shots to maximum effect but Kasatkina broke early in the final set on her way to victory over the world number 11. Sharapova beat Halep at the US Open in August but committed 39 unforced errors in an untidy display in Beijing. The 30-year-old, who returned to competitive tennis in April following a 15-month doping ban, was competing at the China Open for the first time since she won the title in 2014. Now ranked 104th, Sharapova was on court for more than five hours in her first two matches in Beijing, and fatigue from that may have been a factor as Halep broke to love in the first game. Halep dropped just four games overall, and held to love twice in the second set as she went on to serve out the match. Meanwhile, French Open champion Jelena Ostapenko qualified for the eight-player WTA Finals in Singapore this month by beating Sam Stosur 6-3 7-5. Britain's Johanna Konta, who lost in the first round in Beijing and has withdrawn from next week's Hong Kong Open with a foot injury, is in contention for the final place in the Singapore season finale but could face competition from world number 15 Caroline Garcia. France's Garcia - who needs to reach at least the semi-finals this week to keep her chances alive - beat Belgian Elise Mertens 7-6 (7-4) 6-4 on Wednesday. Ukrainian third seed Elina Svitolina also moved to the next round with a 6-4 6-2 win over Australia's Ashleigh Barty, who reached the final of the Wuhan Open at the end of September.