Kristina Mladenovic has reached the BNP Paribas Open semi-finals after beating Caroline Wozniacki 3-6 7-6(4) 6-2 on Thursday.
In seeing off the 2011 Indian Wells winner and 13th seed, the 23-year-old also broke into the top 20 in the WTA Tour rankings for the first time in her career.
Wozniacki rallied from a 4-2 deficit in the second set to force the tie-breaker, but never edged into the lead against Mladenovic.
Leading 2-1 in the third set, Wozniacki then had to have her right foot heavily taped by a trainer.
She then went on to lose the final five games and the match, making the 28th-seeded Mladenovic the lowest seed to reach the semis.
Waiting for Mladenovic in the last four is Elina Vesnina, who claimed a battling win over Venus Williams in their quarter-final tie.