Maria Sharapova escaped with a 6-2 5-7 6-4 victory over Alona Bondarenko of Ukraine on Tuesday in one of eight fourth-round matches at the Pacific Life Open.

The fourth-seeded Russian, who committed 68 unforced errors against Bondarenko in a match that lasted nearly three hours, has now won 17 consecutive matches dating back to last year.

"I felt like I was pretty close to being down and out because I wasn't able to produce good points for a long period of time," Sharapova said.

"I would play a good game, I would get down again and then I would miss three returns in a row. I was just giving her so many opportunities out there."

The 20-year-old lost just her third set this season against Bondarenko and has now won 34 of 37 sets in 2008.

Sharapova, who won this event in 2006, is seeking her 19th career title after winning championships at the Australian Open and Doha earlier this season.

Meanwhile, defending champion and fifth-seeded Daniela Hantuchova continued a streak of her own, winning her ninth successive match at this hardcourt event by defeating India's Sania Mirza in straight sets 6-1 7-6 (7/4).

"I thought it was a great match," Hantuchova said. "Sania is a great hitter. I was expecting really a tough one, and just being able to be in the quarters without losing a set feels really great."

Hantuchova has just three career titles, but two of those trophies have come at this event. Also a winner here in 2002 as a teenager, the 24-year-old Slovakian has won four out of six contests since reaching her first grand slam semi-final at the Australian Open.

One of these streaks will come to an end when Hantuchova and Sharapova meet in the quarter-finals on Wednesday.

"It's going to be an exciting match," Hantuchova said. "She's playing obviously in great form, so it will be a good test for me. I feel like I own this place. I'm here and anything can happen.

"I'm confident, but obviously if I want to win, I have to play my best. Let's see if I will be able to do that."

The runner-up to Sharapova in Melbourne, Ana Ivanovic, has yet to claim a title this season despite reaching a career-high number two world ranking. The 20-year-old Serbian, who reached the quarter-finals here in 2006, moved a step closer to that elusive championship Tuesday by rallying for a 2-6 7-5 6-2 triumph over 13th seed Francesca Schiavone of Italy.

Ivanovic won four out of seven break points and double-faulted just twice in a match that lasted two hours, eight minutes. She won just 18% of her first-return points in the first set and 15% in the second before capturing 10 of 18 in the decisive set.

Russian Vera Zvonareva, the 12th seed, will meet Ivanovic in the quarters after coming from behind to claim a 6-7 (5/7) 6-0 6-4 victory over Casey Dellacqua of Australia.

Zvonareva, who has five career WTA titles, had 11 double faults against Dellacqua but won nine out of 16 break points and 75% (33 of 44) of her first-serve points to escape with the win.

Second-seeded Svetlana Kuznetsova, the runner-up to Hantuchova last season, moved one step closer to her second straight final appearance here with a 6-2 6-3 victory over Caroline Wozniacki of Denmark in their fourth-round match.

The Russian won five out of eight break points and needed just 78 minutes to oust Wozniacki.

Kuznetsova has made two finals this year but still is searching for her first title, having suffered losses to Belgium's Justine Henin and countrywoman Elena Dementieva at Sydney and Dubai, respectively.

The world number three next will face 10th-seeded Agnes Radwanska of Poland, who needed three sets to defeat American Ashley Harkleroad 4-6 6-2 6-4.

Third seed Jelena Jankovic, who also is trying to claim her first title of the year, posted a business-like 6-3 6-3 victory over number 20 Anabel Medina Garrigues of Spain.

The Serbian overcame four double faults by winning 14 of 20 first-return points and six out of eight break points to move on to the quarter-finals here for the first time in seven career appearances.

Jankovic will take on Lindsay Davenport of the United States, who dispatched sixth-seeded Frenchwoman Marion Bartoli 6-2 7-5.

Davenport fired 17 aces in the match, while Bartoli failed to record a single one. The American also won 76% of her first-serve points and four out of six break points.

Not to be outdone by Sharapova and Hantuchova, the 31-year-old Davenport has won eight straight matches overall, including a victory over Olga Gorvortsova in the final at Memphis earlier this month.

Davenport is no stranger to success at this tournament. She won the event in 1997 and 2000 and is a four-time runner-up, with her last final appearance coming in 2005.