Serena Williams [Images] screamed into her fourth Australian Open [Images] final on Thursday, slamming the brakes on Elena Dementieva's [Images] 15-match winning streak.

"A perfect match for me? Oh, no, no, no. But it was definitely better," the American second seed smiled after her 6-3, 6-4 win.

Another Russian stands between Williams and a fourth title at Melbourne Park after Dinara Safina ousted Vera Zvonareva [Images].

Fourth seed Dementieva had not lost on court this year but was no match for Williams on a centre court covered by a roof to keep out the heatwave that is scorching Melbourne.

Meteorologists are predicting the hottest week in a century as the mercury climbs into the 40s each day, buckling railroad tracks and defoliating trees.

Williams kept her cool, though, and cruised past an opponent who had won their previous three meetings.

"I definitely served better," Williams said. "It's so important to serve well against her. She's a really good returner. I moved better and I was definitely more consistent and I kept my cool."

Victory over Safina in Saturday's final will vault Williams back to world number one but the ranking is secondary to her.

RANKING BONUS

"That would be just a bonus," she said. "But my goal isn't to be number one, my goal is to win one more match here at the Australian Open."

Williams has nine Grand Slam singles titles to her name and is desperate to hit double figures.

"I have to go one more. I'm excited that I'm playing really consistent, you know, consistently at least making it to the finals of Grand Slams.

"Obviously I would love to leave a mark and do well, but most of all enjoy myself and do the best that I can do.

"Safina's playing well. She seems to never die. So she's doing a great job.

"She's going to be a tough opponent. She obviously wants to win. She's playing amazing, and she wants to win a Grand Slam and go for the glory."

Safina will be bidding to join big brother Marat Safin [Images] as an Australian Open champion and a world number one -- a ranking she will attain if she beats Williams.

On Thursday she also snapped a three-match losing streak against her opponent to advance to her second Grand Slam final after last year's French Open.

The combination of Safina's heavier shot-making and aggression proved too much for her fellow Russian as she closed out victory 6-3, 7-6 in one hour and 46 minutes.

SAFINA'S IDOL

"Since I was growing up it has been my dream one day to be number one," Safina said in a courtside interview. "To play against Serena and to fight for the number one is just going to be unbelievable.

"I just hope it will be a good match that we can all enjoy and whoever wins, we'll shake hands at the end of the match and say 'well you deserve to be number one'.

"I watched my brother on TV winning this tournament and even when I watch it now I have tears in my eyes," Safina said of Marat's 2005 feat.

"It is great that I can follow his footsteps because he was my idol and he is still my idol. That I'm doing as well as him is just amazing."

Roger Federer [Images] takes on Andy Roddick [Images] in the first men's semi-final later on Thursday. Rafa Nadal and Fernando Verdasco contest the second semi-final on Friday.

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