World number two Victoria Azarenka survived a scare before reaching the fourth round of the BNP Paribas Open with a three-set win over Kirsten Flipkins.
Azarenka lost the opening set 6-3 before storming back against the Belgian to take the next two 6-3 6-0.
Meanwhile, former world number one Caroline Wozniacki eased to a 6-2 6-1 win over Elena Vesnina at the BNP Paribas Open in Indian Wells.
Wozniacki, enjoying better form these days, took the first set in little more than 40 minutes after being far more effective on her serve.
The seventh seed, broke at the start of the second set and moved into a 3-0 lead and her opponent could only take one game before going down in one hour 15 minutes.
However, another former world number one, Ana Ivanovic, who has also shown glimpses of her best recently fell to a 1-6 6-3 6-0 loss to Germany’s Mona Barthel.
The Serb looked on course for a routine win when he took the first set for the loss of only a game, but after losing a close second set – her game fell away dramatically in the decider.
Seventh seed Sam Stosur beat Peng Shuai 6-3 3-6 6-2 in two hours and 12 minutes. Both players struggled for consistency with their serves but it was Stosur who prevailed.
There were also wins for Angelique Kerber, Nadia Petrova Garbine Muguruza and Urszula Radwanska.