Almost impossible to beat me: Serena

Serena Williams says she is impossible to beat at times, and there are a few people who might now be tempted to agree.

The former world number one has silenced the critics who suggested she is a spent force by advancing to an all-American final at the Australian Open, where she plays top seed Lindsay Davenport on Saturday.

As much as anything it is the manner in which six-time Grand Slam title winner Williams won through to her showdown with Davenport that should eradicate any lingering question marks over her competitive hunger.

Facing match-point on three occasions in her semi-final with Maria Sharapova, she stared down the challenge nervelessly and clawed her way back from the brink of defeat for a 2-6, 7-5, 8-6 victory.

The 23-year-old American insists she has nothing to prove to anyone, and has bristled throughout the past fortnight at the notion her tennis star is on the wane as she chases her first Grand Slam title since Wimbledon in 2003.

But she admitted on Friday that coming through her ordeal of fire against Sharapova, who had beaten Williams in the Wimbledon and WTA Championship finals last season, had been doubly satisfying.

"When you're winning matches 6-2, 6-1 you feel better — you're not sore, you feel fresh, you're body's good," Williams said. "But when you're winning 8-6 in the third after saving three match-points, it's even better.

"In that sense I've played some tough matches in the past year and I haven't been able to win them all. It was a good feeling to come through that."

It was the second time Williams had saved match-points in an Australian Open semi-final following a similar escape act against Kim Clijsters in 2003, and reinforced her stated view that she remains the "top fighter out there."