INDIAN WELLS, Calif. -- Maria Sharapova defeated Victoria Azarenka 6-4, 6-3 on her sixth match point in a third-round pairing of former No. 1-ranked players at the BNP Paribas Open on Monday.
Sharapova hit 23 winners, one more than Azarenka, and had 10 fewer unforced errors than Azarenka's 37 to even their all-time series at seven wins apiece.
Azarenka fought off four match points on her serve in the eighth game to hold trailing 5-3. They dueled through five deuces until Azarenka fired a big serve to keep herself in the match.
Sharapova took a 40-15 lead to set up her fifth match point, but netted a forehand. She converted on her sixth one with a shot that Azarenka couldn't return near the net.
Sharapova, a two-time champion at Indian Wells, will meet defending champion Flavia Pennetta in the fourth round. Seeded 15th, Pennetta beat Sam Stosur 6-4, 6-2 on an outside court.
Azarenka, who beat Sharapova for the title here in 2012, is just starting to return to form after a left foot injury limited her to nine tournaments last year and dropped her ranking to 32nd. The two-time Australian Open champion led 4-3 in the first set before Sharapova won the final three games.
Two more former Indian Wells champions and top-ranked players went out in the third round. Fourth-seeded Caroline Wozniacki lost to 31st-seeded Belinda Bencic, 6-4, 6-4, and fifth-seeded Ana Ivanovic lost to 25th-seeded Caroline Garcia 6-2, 5-7, 6-2.
Bencic earned her first win over a top-five player and at 18 became the youngest player to reach the fourth round this year. Last year in Istanbul, Bencic failed to win a game off Wozniacki.
"In Istanbul I had maybe too much respect and I was afraid, nervous," she said. "Today I really had a good game plan. I served well kind of, and had sometimes some easy points on my serve because of that."
In other women's matches, No. 6 seed Eugenie Bouchard beat CoCo Vandeweghe 6-3, 6-2 and qualifier Lesia Tsurenko defeated 20th-seeded Alize Cornet, 7-5, 1-6, 6-2.
Andy Murray outlasted Philipp Kohlschreiber 6-1, 3-6, 6-1 in a nearly two-hour baseline slugfest under a hot sun. Murray earned the only two breaks of the third set and closed out the win when Kohlschreiber's forehand went wide, one of 35 unforced errors by the German. The temperature topped 90 degrees (32 Celsius), unusually warm for this time of year.
Cool mornings, hot afternoons and warm evenings have made for changing court conditions and ball speed in the desert, and Murray was affected by them.
"When you are playing in those matches during the heat of the day, you need to trust your shots. You need to go after them, because if you back off and try and sort of guide the ball in these conditions, it doesn't work," he said. "During the day it's ridiculous how high the balls bounce and how quick they move through the air and jump off the court."
Murray moved on to a fourth-round match against Adrian Mannarino, who beat 14th-seeded Ernests Gulbis, 6-4, 6-4.
Fifth-seeded Kei Nishikori was stretched to three sets before overcoming Fernando Verdasco, 6-7 (8), 6-1, 6-4. Nishikori double-faulted twice in the final game before advancing to the fourth round for the first time in his seventh appearance at Indian Wells.
"Third set, it could go both ways, but I got first break," Nishikori said. "I really served well. Until last game I didn't face break points. It was still close the last game, so really happy to beat Fernando."
John Isner beat 18th-seeded Kevin Anderson, 7-6 (8), 6-2, setting up a possible fourth-round match against top-ranked Novak Djokovic, who played Albert Ramos-Vinolas in a night match.
Isner has lost just 12 points on his big serve in his first two matches.
"Winning that, it's pretty big for my confidence," he said. "Serve came up huge when I needed it in the first-set tiebreaker. 146 right on the line, and I just gutted it out and I played a good second set."
Jelena Jankovic, who won here in 2010 and spent 18 weeks at No. 1 in the world, outlasted Madison Keys, 5-7, 6-4, 6-3 despite the Serb having just 13 winners and 42 unforced errors.
Jankovic is coming off a back injury and torn muscle in Doha, which hampered her practice schedule.
Keys, a 20-year-old American coached by former top-ranked Lindsay Davenport, had her chances to take control, leading 3-1 in the final set. She hit 39 winners, but came undone with a whopping 64 unforced errors.