INDIAN WELLS, Calif. — Elena Vesnina recovered after blowing three match points to beat Venus Williams 6-2, 4-6, 6-3 and reach the semifinals of the BNP Paribas Open on Thursday night.

Vesnina staved off six break points in the last game, closing out the 71-minute match with two forehand winners. Williams overcame three match points on her serve on three straight errors by Vesnina in the eighth game that featured six deuces and lasted for 9½ minutes.

Vesnina had 38 unforced errors and eight double faults; Williams had 47 unforced errors and seven double faults.

The 14th-seeded Russian takes on No. 28 seed Kristina Mladenovic in the semifinals. Mladenovic beat Caroline Wozniacki 3-6, 7-6 (4), 6-2 to break into the top 20 in the WTA Tour rankings for the first time in her career.

No. 3 Karolina Pliskova and Svetlana Kuznetsova are set for the other semifinal.

Vesnina defeated No. 2 Angelique Kerber 6-3, 6-3 in the quarterfinals and is already assured of her best result in nine appearances at the desert tournament.

Williams needed three sets to win two of her first three matches at Indian Wells, where she was playing for the second time after a 15-year boycott because of a hostile crowd reaction she received in 2001 after withdrawing with an injury from a semifinal against younger sister Serena.

She started slowly against Vesnina, repeatedly struggling with her service toss while piling up errors.

Neither Mladenovic nor Wozniacki had dropped a set before their quarterfinal. Wozniacki rallied from a 4-2 deficit in the second set to force the tiebreaker, but the former world No. 1 and 2011 Indian Wells winner never led in the tiebreaker.

Wozniacki held for a 2-1 lead in the third set and then had her right foot heavily taped by a trainer. She went on to lose the final five games and the match, making the 28th-seeded Mladenovic the lowest seed to reach the semis.

"I didn't break her when I had the opportunity," Wozniacki said. "I didn't hold when I had the opportunity and all of sudden those games kind of slipped away. She had some big forehands when she needed to and then I see myself down 5-2, and it could maybe have been different."

There were 11 service breaks in the 2½-hour match played in 91 degree (32 C) heat.

Besides moving up in the world rankings, Mladenovic becomes the new No. 1 in France, overtaking countrywoman Caroline Garcia by virtue of her results in the desert.

"I see that it's paying off, that the results are coming," Mladenovic said. "The ranking is just the consequence of all the work you put on a daily basis. Eventually, you're playing those great matches better and better and give yourself a chance to win them, and then the ranking obviously follows."

In a match involving the two lowest remaining men's seeds, No. 21 Pablo Carreno Busta of Spain edged 27th-seeded Pablo Cuevas of Uruguay, 6-1, 3-6 7-6 (4).

Carreno Busta saved two match points in the third, including when Cuevas fell on a backhand leading 5-4, 4-30.

Cuevas tied it 3-all in the tiebreak before Carreno Busta won the final five points to close out the two-hour match.

"With Pablo I need to be very focused on my game, very aggressive, because his second serve or his kick, the ball bounce a lot," Carreno Busta said of his sometime doubles partner. "So I need to be aggressive and I need to dominate the points because he's really dangerous with his forehand."

It was the biggest singles quarterfinal of their respective careers. Carreno Busta had not reached that stage of a Masters 1000 event in 17 previous tries; Cuevas hadn't been there in 29 tries.

Carreno Busta avenged his loss to Cuevas in the Sao Paulo semifinals on March 6 and in the process snapped Cuevas' seven-match winning streak.

Carreno Busta will play either No. 3 Stan Wawrinka or No. 8 Dominic Thiem, who met in an evening quarterfinal.