Roger Federer [Images] faces his first serious test of his Australian Open defence when he locks horns with Andre Agassi [Images] in a mouth-watering quarter-final on Tuesday.

The world number one is a hot favourite to win the tournament and has not dropped a single set all week but Agassi, a four-times champion at Melbourne Park, promises to test him.

"I'm looking forward to the challenge and the opportunity of playing Roger," Agassi said.

"He's been playing the best tennis in the world for a while now but somebody has to beat him sooner or later, right? I hope it's Tuesday night."

Agassi won his first three matches against Federer but the Swiss master has won the last four, including an epic five-setter in the semi-finals of last year's US Open and says he is confident of making it five in a row.

"I know I can beat him. He's not as good as he was when he was at the top of the ranking, otherwise he would be there," Federer said.

"Fortunately, I'm there. I think he has to raise his game, not me."

The build-up to Tuesday's match has got everyone talking and Andy Roddick [Images], the world number two, said he wouldn't miss it for the world.

"I'm as excited as the next person," Roddick said. "I'm still a big tennis fan so I'm excited to watch it, that's for sure."

RUSSIAN WOMEN

Awaiting the winner is a semi-final against either Marat Safin [Images] or Dominik Hrbaty, who meet in the first of Tuesday's two men's quarters. The pair have met 12 times for six wins apiece.

Hrbaty beat 2002 Australian Open champion Thomas Johansson to book his place in the last eight while Safin won three tiebreaks to beat Olivier Rochus in four sets.

Safin made the final last year after surviving a series of gruelling matches but was too exhausted to mount any real challenge to Federer so is trying to conserve his energy this time.

"This week has been a little bit easier. I'm playing a little bit smarter and I'm just trying to save my time on the court," the Russian fourth seed said.

"It's a long tournament and there is no need to waste the energy on something that you don't have to."

A fascinating confrontation looms in the women's quarter-finals with Wimbledon champion Maria Sharapova [Images] meeting US Open champion Svetlana Kuznetsova in an all-Russian affair.

Russian women have won the last three Grand Slam titles and looked to be in with a great chance of completing a sweep of the four majors when seven made it through to the last 16.

But Sharapova and Kuznetsova were the only two to survive and the winner of their match will be left flying the flag.

GREAT MATCHES

Adding spice to their meeting is that the pair have never been the closest of friends though Kuznetsova was keen to hose down any talk of a rift.

"I think she's all right. She's a bit different, like each of us, we are all different," Kuznetsova said.

"Nobody does nothing against her. I don't mind as long as we defend the colours of our country."

The winner of the all-Russian match will play either Serena Williams [Images], the 2003 Australian Open winner, or French world number two Amelie Mauresmo after they meet in Tuesday's second women's quarter-final.

Williams has won eight of her previous nine matches with Mauresmo but says she's expecting a tough match.

"I actually really like playing her. We've had some great matches and she definitely brings out some great shots," Williams said.

"She hits some great shots and plays some great tennis. I definitely think I bring out the best in her as well."

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