INDIAN WELLS: Second-seeded Novak Djokovic has survived a scare, but it was smooth sailing for defending champion Rafael Nadal as both moved into the fourth round of the BNP Paribas Open.

Serbia's Djokovic saved three match points en route to a 6-3, 2-6, 7-6 (7/3) victory over Germany's Philipp Kohlschreiber on Monday and said he'd have to do better to add a second Indian Wells title to the one he captured in 2008.

After breaking in the first game of the second set and holding for a 2-0 lead, Djokovic dropped the next nine games and found himself fighting to stay alive.

"Nine games in a row, this is something that I cannot allow anymore to happen," said Djokovic, who was pleased that he managed to play well with his back to the wall but puzzled as to why he couldn't do it throughout the match.

"He could easily be the winner of this match, and he would deserve it," Djokovic said.

Djokovic stopped the rot when he held serve to narrow the gap in the third set to 3-1, but even after he had reeled off four games in a row, Djokovic wasn't out of the woods.

Kohlschreiber broke him again to level the set at 4-4 and had Djokovic on the ropes - down 4-5 and 0-40 on his own serve.

An overhead winner from Djokovic and a wayward backhand from Kohlschreiber took care of two of Kohlschreiber's match points.

The two then battled through a long rally that ended when Kohlschreiber netted a backhand off a blistering forehand from Djokovic.

Djokovic gave himself some breathing space with an ace, but promptly double-faulted before finally holding serve.

In the tiebreaker, Djokovic seized control quickly, taking a 4-0 lead and closing out the contest on his first match point.

"I just don't understand why I didn't do that throughout the whole match. It was all my fault, and I put him back into the play," Djokovic said. "He regained the rhythm, and he was just a point away from the victory. So these things frustrate me a little bit."

Nadal, the third seed behind Roger Federer and Djokovic, had nothing to be frustrated about as he dispatched Croatian Mario Ancic 6-2, 6-2 in little more than an hour.

Nadal never faced a break point, and broke Ancic in the first and seventh games of each set.

"I think I am playing at the good level with my forehand. When I touch the ball, all the time I try to do something - playing aggressive, playing long, changing the direction. I am doing that well here."

Women's third-round action featured a see-saw battle between sixth-seeded Serbian Jelena Jankovic and Italian Sara Errani, in which Jankovic emerged with a 2-6, 7-6 (8/6), 6-4 victory after two hours and 48 minutes.

Jankovic trailed 2-4 in the third set - and was one point away from falling 2-5 behind - but won the last four games to put it away.

"At the end I was able to win," Jankovic said. "That's the most important thing."

Third-seeded Victoria Azarenka of Belarus couldn't say the same, falling 7-6 (7/4), 6-2 to Spain's Maria Jose Martinez Sanchez.

Eighth-seeded Australian Samantha Stosur and defending champion Vera Zvonareva set up a fourth-round meeting.

Stosur beat Russian Anastasia Pavlyuchenkova 6-3, 6-0, while Zvonareva downed Latvia's Anastasija Sevastova 6-2, 6-3.

Carla Suarez Navarro - the Spaniard who ousted top-seeded Svetlana Kuznetsova in the second round - also advanced, beating Hungary's Agnes Szavay 6-4, 3-6, 6-1.