Seventh-seeded Maria Sakkari of Greece kept her WTA Indian Wells 1000 title hopes alive by battling back to beat Ukrainian Anhelina Kalinina 3-6 6-2 6-4.

Sakkari drew Kalinina to the net with a drop shot and then fired a backhand winner down the line on match point to complete the comeback.

The Greek leaned over and pumped her fists in celebration after sealing the win on a hot day in the Southern California desert.

"I don't mind winning ugly," she told reporters.

"It doesn't really matter. I just give myself another chance to play better the next day."

Sakkari, a finalist in Indian Wells last year, will next face 17th seed Karolina Pliskova in the round of 16 after the Czech beat Russia's Veronika Kudermetova 6-1 7-5.

Third-seeded American Jessica Pegula edged Russia's Anastasia Potapova 3-6 6-4 7-5 to set up a meeting with Petra Kvitova after the 15th-seeded Czech won a rollercoaster match against Jelena Ostapenko 0-6 6-0 6-4.

Sweden's Rebecca Peterson dispatched Jil Teichmann of Switzerland 3-6 6-3 6-1, 16th seeded Czech Barbora Krejcikova beat China's Wang Xinyu 6-2 7-6 (7-1) 6-2, and sixth-seeded American teenager Coco Gauff beat Czech Linda Noskova 6-4 6-3.

Belarusian second seed Aryna Sabalenka advanced via walkover when her Ukrainian opponent Lesia Tsurenko withdrew.