DOHA, Qatar (AP) Third-seeded Agnieszka Radwanska came through a tough first set before beating Monica Niculescu 7-5, 6-1 on Wednesday to reach the quarterfinals of the Qatar Open.
Radwanska, who was down a double break in the first set, struggled with her first serves. But as the match progressed, her superb shot-making rarely her Romanian opponent much chance.
Also advancing from the third round was fourth-seeded Garbine Muguruza of Spain, who beat Timea Babos of Hungary 6-2, 7-5.
However, fifth-seeded Petra Kvitova of the Czech Republic lost 5-7, 6-2, 6-1 to Jelena Ostapenko of Latvia.
Kvitova, a two-time Wimbledon champion, came from 3-1 down to win the first set, but Ostapenko continued to play with confidence. She hit 28 winners before wrapping up the match in one hour and 56 minutes.