INDIAN WELLS, CALIFORNIA (AFP) - Three-time Grand Slam champion Angelique Kerber came from a set down against qualifier Natalia Vikhlyantseva on Monday to reach the WTA Indian Wells fourth round.
Eighth-ranked Kerber, a two-time semi-finalist in the California desert, shook off a slow start to beat the 112th-ranked Russian 3-6, 6-1, 6-3.
After dropping her serve in the first game of the second set, Kerber won seven games in a row to force a third set and take a 2-0 lead in the decider.
She was unable to convert four match points against Vikhlyantseva's serve at 5-1 and was broken at love when serving for the match at 5-2 before finally putting it away.
Defending champion Naomi Osaka, whose Australian Open triumph propelled her to number one in the world, headlines the battles for a place in the round of 16 when she takes on American Danielle Collins in the night session on Stadium Court.
Osaka opened her campaign with a straight-sets victory over Kristina Mladenovic, avenging her shock loss to the French player at Dubai in February.
Collins is trying to build on a breakout run at the Australian Open, where she fell in the semi-finals to two-time Wimbledon champion Petro Kvitova.
Osaka won their only prior meeting in Beijing last year 6-1, 6-0, a result that left Collins eager for "another crack" at the world number one.
"There is no way it could go any worse for me," Collins said. "That's really as bad as it can get in terms of the score and how quickly the match went." Fifth-seeded Czech Karolina Pliskova survived an off day to reach the round of 16 with a 6-3, 6-2 victory over Belgian qualifier Ysaline Bonaventure.
"The only good thing was my serve today, with a lot of aces and service winners," Pliskova said.
"Overall, I think my game was a bit bad. The conditions changed from my last match, but hopefully in the next match I can play better." Whatever her struggles, Pliskova - winner of her 12th WTA title at Brisbane in January and a semi-finalist at the Australian Open - needed just 66 minutes to get past Bonaventure.
In her next match, she said, she'll "have to be more careful".
That will be against Estonian Anett Kontaveit, who was leading 5-0 against 11th-seeded Anastasija Sevastova when the Latvian retired from their match.