Roger Federer [Images] and Rafael Nadal [Images] remain on course for a showdown in the final of the Rome Masters after they both enjoyed comfortable wins to reach the last eight on Thursday.

World number one Federer brushed aside Radek Stepanek 6-1, 6-4 and defending champion Nadal extended his unbeaten run on clay to 50 matches with a near-flawless display to beat Tim Henman 6-2, 6-2.

They were joined in the quarter-finals by fourth seed David Nalbandian, who beat qualifier Alberto Martin 7-5, 6-4, and fifth seed Andy Roddick [Images], who knocked out Greg Rusedski [Images] 7-6, 6-2 to guarantee his best finish in Rome since reaching the semi-finals four years ago.

"On grass, it's pretty simple: I'm just going to hit the ball pretty hard and try to get depth," Roddick said.

"Here, I've got to figure it out a little bit more with pace, varying shots, kind of play against my nature a little bit. It's frustrating at times, but it's also a fun challenge."

Czech Stepanek offered little resistance to Federer and made a succession of unforced errors to surrender the first set in 22 minutes.

He steadied himself in the second, but never looked likely to get back into the contest after dropping serve in the third game.

"He never really got close to my serve, and that made the match go so easy and so quick really," said Federer, who has yet to drop a set in the tournament.

He next plays Spanish qualifier Nicolas Almagro, who advanced when sixth seed Nikolay Davydenko retired injured after a set of their third-round match.

Most neutrals are already anticipating a Federer-Nadal final. The Swiss has lost their last three meetings and asked what aspect of his game he needed to raise to beat Nadal, he replied: "I'll definitely have to improve things if I want to go extremely far here.

"But, you know, there's not much I'm doing wrong really. I'm playing very good from the baseline.

"Maybe I could concentrate a little bit more on my serve."

Nadal, meanwhile, was looking forward to his quarter-final against 10th seed Fernando Gonzalez, who has won both their previous matches, the last two years ago.

"It will be a tricky match but, you know, it is a long time since I played him. I think I have got a bit better since then," the 19-year-old Spaniard said.

While the spotlight remains fixed on the top two, Nalbandian has emerged as the player most likely to cause an upset.

The Argentine, winner of last week's claycourt event in Estoril, is set for a semi-final meeting with Federer, whom he has beaten in six of their 10 head-to-heads.

Before that, he must get past Croatia's Mario Ancic, who beat Ruben Ramirez Hidalgo 6-3, 6-7, 7-5.

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