By Ian Ransom

MELBOURNE, Jan 23 - Iron-woman Francesca Schiavone survived the longest grand slam women's singles match in the professional era on Sunday, edging past Svetlana Kuznetsova after four hours 44 minutes to reach the Australian Open quarter-finals.

The 30-year-old Italian, who won last year's French Open in front of a fan club wearing T-shirts with the slogan "Schiavo Nothing Is Impossible," was on the brink of defeat at one point but fought off six match points before prevailing 4-6 6-1 16-14 on Hisense Arena.

An enthralling match began in bright sunshine and ended in the gloaming with both players exhausted and requiring visits from the trainer, however it was Schiavone who found the reserves of energy to break decisively at 14-14.

She sealed victory with a forehand volley at the end of a deciding set that lasted three hours -- a long way short of the more than eight hour monster contested by John Isner and Nicolas Mahut at Wimbledon last year but remarkable all the same.

"I hope one day to show this DVD to my son," said Schiavone, who became the second oldest player to win a maiden grand slam when she beat Australia's Samantha Stosur at Roland Garros last year.

"It's like every point is match point. You have to keep going. You know that physically you are tired, but the other one is too.

"Mentally it's the same ... We work every day to do this, to give the best when you really say, 'no, I can't do it.'

"But at the end you have something more, always."

Kuznetsova also saved two match points, the first with a baseline winner and the second with a sharp return that scorched her opponent's shoelaces, but could not grind down the the feisty Italian net-rusher.

"I just feel very empty. I don't know what to say," she said. "We both fought so hard the whole match, and the important moments she just played better.

"But statistically I also felt like I was the better player on the court ... Just very disappointing."

The match surpassed the four hour 19 minute slog between Czech Barbora Zahlavova-Strycova and Russia's Regina Kulikova at last year's Australian Open and fell one short of the 48-game record set by American Chanda Rubin and Spain's Arantxa Sanchex-Vicario, also at Melbourne Park.

Lop-sided one-hour romps have been the rule rather than the exception in the women's tournament at Melbourne Park this year, but the fourth-round classic was full of twists and turns.

Kuznetsova hit back hard after conceding a tight first set, breaking Schiavone three times but nervelessly holding her own serve to set up a memorable decider.

The two-times grand slam-winning Russian had her chance to sew up the match at 8-7 when she thumped a huge forehand winner down the line to bring up three match points, but threw two away with loose strokes and lost the third from a sharp return.

"I tried to ask the umpire -- 'please give me this point, I need it.' But he didn't give (it to) me," she said.

Trainers worked feverishly on the players in a break at 10-10, but it was not until 14-14 that Schiavone captured the decisive break, lunging for a desperate cross-court volley that left Kuznetsova flat-footed at the net.

Italy's first grand slam champion Schiavone, who won a 9-7 third set against Canada's Rebecca Marino in the second round, will meet top seed Caroline Wozniacki in the quarter-finals.

"If you ask me now, I say no," said the Italian, when asked if she had much left in the tank.

"But, yeah, I'm young. I can run. I can do anything. For Tuesday I will be -- I don't know how, but it will be good. Why not?"

After all, for Schiavone it seems nothing is impossible.

(Editing by John O'Brien and Martyn Herman)