Indian Wells: Defending champion Caroline Wozniacki recovered from a shaky opening set to battle past Swede Sofia Arvidsson 3-6, 7-5, 6-2 in the third round of the Indian Wells WTA tournament on Monday.

Wozniacki, who beat Frenchwoman Marion Bartoli in last year's final, initially struggled to hold serve on a cool evening but found her form to break her opponent three times in the final set and seal victory in two hours, 37 minutes.

The 21-year-old Dane, wearing an orange dress and matching visor, pumped her left fist in delight after pouncing on a drop shot and unleashing a crosscourt backhand winner to break the Swede and lead 5-2.

Fourth-seeded Wozniacki then coolly served out for victory, ending the match with a forehand winner after Arvidsson had again teased her forward with a drop shot.

"I knew it was going to be a tough match," a smiling Wozniacki said in a courtside interview at the Indian Wells Tennis Garden after a marathon baseline battle between the two Scandinavians.

"I've known Sophia since I was 12 or 13 and we know each other's games so well.

"She just came out from a win in Memphis and I knew she was on fire. I'm so happy with this win," added the Dane, who will next play Serb Ana Ivanovic, a 6-7 6-3 6-2 winner against Kazakhstan's Ksenia Pervak.

Arvidsson, through to the third round at Indian Wells for the first time in five attempts, won a topsy-turvy opening set that ended with three successive breaks of serve, two of them in the Swede's favour.

Both players struggled to hold service in the second set with four breaks in the first six games before Wozniacki took control. She broke Arvidsson to love in the 11th game and then held to level the match after the Swede hit a forehand long.

The Dane made a fast start to the third set, breaking her opponent in the first and third games to lead 3-0 before Arvidsson broke back to love in the fourth after Wozniacki double-faulted.

The next two games went with serve until the Dane broke the Swede in the seventh, chasing down a poorly executed drop shot and hitting a backhand crosscourt winner to lead 5-2.

Wozniacki, a winner of 18 WTA titles, held serve in the eighth to improve her career record against Arvidsson to 5-2.