Nadal, Federer race into last 16 at Wimbledon

World number one Nadal wrapped up a straight sets win over Luxembourg's Gilles Muller in a match that had been halted on Friday because of rain, winning 7-6 (8/6), 7-6 (7/5), 6-0.

The reigning champion, who will face Juan Martin Del Potro in the last 16, was in imperious form against Muller, totting up only three unforced errors as he breezed into the fourth round.

But Nadal is under no illusions about the scale of the task facing him in the second week of Wimbledon fortnight, saying the depth of talent in this year's draw made it one of the most unpredictable men's tournaments ever.

"You never know what's going on," Nadal said. "It seems like the best players are playing well. I don't know if I'm gonna win next round, so probably the rest of the players think the same."

Federer, who is bidding to win a record seventh Wimbledon title, romped into the fourth round with a brisk straight sets dismissal of Argentinian 28th seed David Nalbandian, winning 6-4, 6-2, 6-4.

Third seed Federer has not won a Grand Slam title for 18 months but showed the sort of form which suggests a record 17th major title is well within his capability over the coming week.

The Swiss former world number one, whose last triumph at Wimbledon came in 2009, was satisfied with his performance as he advanced to a meeting with Russian 18th seed Mikhail Youzhny.

Federer insisted he remained as hungry as ever to reclaim his Wimbledon crown. "The day after my victory, the day after my final losses, I've been hungry," Federer. "It doesn't come in phases, I'm always hungry."

The 29-year-old is also unconcerned by the fact that his last Grand Slam win came at the Australian Open in 2010.

"It hasn't been that long," Federer said. "I don't go through days thinking 'God I haven't won a Grand Slam in so long.' You don't cry over stuff like that.

"You guys bring it up and I answer the question. That's it. But I don't get pulled down by it. Actually I think I get motivation from it."

Second seed Novak Djokovic survived a scare in the final match of the day, winning 6-4, 4-6, 6-3, 6-4 in a thrilling four-set battle with 32nd seed Marcos Baghdatis of Cyprus.

Djokovic was given a warning after smashing a racquet in frustration during a pulsating Centre Court encounter with Baghdatis, a beaten semi-finalist here in 2006.

Djokovic, who faces France's Michael Llodra in the last 16, was relieved to have emerged victorious from a testing enounter.

"To pull a win out of this game was great," he said. "Today wasn't my day totally but when I needed to I played some good shots."

The shock of the day saw fifth seed Robin Soderling bundled out by Australian teenager Bernard Tomic. Tomic, who this week replaced Lleyton Hewitt as Australia's number one, swept aside his Swedish opponent 6-1, 6-4, 7-5.

Tomic now faces Xavier Malisse in the last 16 after the Belgian veteran accounted for Austrian 11th seed Jurgen Melzer 7-6 (7/5), 6-3, 6-0.

Another seeded casualty was France's Gael Monfils. The ninth seed tumbled out 6-3, 3-6, 6-3, 6-3 against Polish qualifier Lukasz Kubot.

In other matches Saturday, Mardy Fish ensured the United States will be represented in the last 16 following the shock exit of Andy Roddick, when Dutch opponent Robin Haase retired as he trailed by two sets to one.

Czech sixth seed Tomas Berdych, the 2010 runner-up, accounted for another American, waltzing past Alex Bogomolov Jr 6-2, 6-4, 6-3.

Elsewhere there were wins for seventh seed David Ferrer, who downed Slovakia's Karol Beck 6-4, 6-3, 6-3 while Jo-Wilfried Tsonga beat Fernando Gonzalez 6-3, 6-4, 6-3.

Asian representation in the men's tournament ended however as Taiwan's Lu Yen-Hsun bowed out against French 19th seed Llodra, losing 6-3, 6-3, 6-1.