Roger Federer emphatically extended his dominance over long-time rival Lleyton Hewitt to cruise into the Australian Open quarterfinals on Jan. 25.

The Swiss top seed was at a different level to the big-hearted Australian 22nd seed in their 25th meeting as he rolled out a 6-2, 6-3, 6-4 win in one hour, 55 minutes.

Federer further underlined the gulf with Hewitt as he claimed his 15th straight victory but his next opponent Nikolay Davydenko has beaten the 15-time Grand Slam champion at their past two meetings.

It looms as Federer's first major challenge in the year's opening Grand Slam.

"Nikolay's one of the good return players in the game. He moves extremely well and makes it hard," Federer said.

"I'm in for a good match for sure. I favor my chances in a best-of-five set match. We'll see how it goes."

For Davydenko's part, Federer will be the obvious favorite in their match.

"He's always for me the favorite," he said. "But when I'm on the court, I try to change my mind. If I feel I have a chance to win a set and the next set I then realize that's what I did against him in our past two matches."

Federer was typically gracious in victory, saluting Hewitt, with their rivalry stemming back to their junior playing days.

"I always think the matches are extremely tough. Physically and mentally very challenging," Federer said.

"You're always going to be caught up in quite a tough match against him and even though the scoreline predicts something else, I had to really dig deep and come up with some amazing shots to beat him.

"I was really able to press on the offensive, serve well when I had to and I moved well. Overall I'm extremely happy."

There was just one momentary spark to fire up the willing home crowd when Hewitt broke Federer's service for the only time in the eighth game of the third set.

But the Swiss great unleashed a sensational forehand cross-court volley to immediately break back in the next game.

It lifted his imposing record over former world No 1 Hewitt to 17-8.

Hewitt's last victory against Federer came seven years ago in a Davis Cup tie here when Federer led two sets to love and 5-3 in the third before the Australian stormed back to win in five sets.

Yesterday's victory was Federer's 51st at the Australian Open with just seven defeats.