Top seed Simona Halep narrowly avoided an upset in the BNP Paribas Open third round, digging deep for a 1-6 7-6 (7-3) 6-2 win over world No 165 Caroline Dolehide.
Romanian Halep was outplayed by American Dolehide in the first set but slowly exerted her authority and, after surviving a second-set tiebreak, gradually wore down the tiring teen to secure victory.
Another American teenager Amanda Anisimova claimed the biggest win of her career by dumping out two-time Wimbledon champion Petra Kvitova.
Contesting just her fifth professional match, 16-year-old Anisimova played well above her world ranking of 149 to win 6-2 6-4 in just over an hour in Indian Wells.
Kvitova came into the event on a 14-match winning streak, the joint-longest of her career, after claiming back-to-back titles in St Petersburg and Doha.
But she was brought down to earth with a bump by wild card Anisimova, who has yet to drop a set and becomes the first 16-year-old to reach the fourth round at Indian Wells since 2005.
"I'm still in shock," Anisimova said. "She's the best player I have ever played, and it was the biggest court I have ever played on."
French Open champion Jelena Ostapenko, seeded sixth, was beaten 6-3 6-3 by Croat Petra Martic, while French 14th seed Kristina Mladenovic was also sent packing in straight sets, going out 6-1 6-2 at the hands of China's Wang Qiang.
US Open champion Sloane Stephens enjoyed a satisfying second-round win over Victoria Azarenka, who beat the American three straight years at the Australian Open from 2013-15.
"I was a little more aggressive," said Stephens, who won 6-1 7-5. "These courts suit my game really well. I was super focused on just playing my game and making sure I was executing."
You can watch the ATP Masters 1000 from Indian Wells on Sky Sports Arena and via the red button from 6pm on Monday. You can also watch it from 11pm on Sky Sports Main Event.
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