LONDON, June 29- Roger Federer, Rafael Nadal and Andy Murray were all in imperious form as they surged into the Wimbledon quarter-finals on Monday, but three-time finalist Andy Roddick crashed to a stunning defeat against Taiwan's Lu Yen-Hsun.
Swiss top seed Federer, who is gunning for a seventh Wimbledon title, blasted away the doubts after a pair of disappointing displays in the first week as he cruised to a 6-3, 6-2, 6-3 win over Austrian 16th seed Jurgen Melzer on Centre Court.
Joining Federer in the last eight was second seed Nadal, the 2008 Wimbledon champion, who shrugged off concerns over his fitness after thrashing France’s Paul-Henri Mathieu 6-4, 6-2, 6-2.
Nadal, who plays Robin Soderling next in a rematch of the recent French Open final, has been troubled by a right knee injury and is set to have treatment on it once the tournament ends.
But he looked in good shape during a two hour demolition of the unseeded Mathieu on Court One and insisted he was fine after the match.
There was a major shock late in the day as Roddick, beaten by Federer in last year’s final here, failed to get past a player ranked 84th in the world and competing in his first Grand Slam quarter-final.
It was an historic victory for Lu, who became the first Taiwanese man or woman to reach the quarter-finals of a Grand Slam singles.
That result was a boost to Federer, who could have played Roddick in the last four, and the Swiss admits he is in fine form at present.
"I felt great. It was always going to be a tough match against Jurgen," Federer said.
"I found my range and I was playing well and very happy with the way I played. This is a very good win for me.
"I think my form’s good now and that’s what I really care about. I know how to win here and that’s a great advantage for me."
Federer faces Tomas Berdych in the quarter-finals after the Czech 12th seed came from behind to beat Germany’s Daniel Brands 4-6, 7-6 (7/1), 7-5, 6-3.
Brands made it through to the fourth round after Romania’s Victor Hanescu pulled out of their third round tie in controversial circumstances.
Hanescu was fined for spitting towards the crowd and not trying as he threw in the towel in the fifth set.
Elsewhere at the Championships, Murray defeated American 18th seed Sam Querrey 7-5, 6-3, 6-4 to revive a nation’s sporting hopes after England’s dismal defeat to Germany in the football World Cup.
Just 24 hours after England flopped in South Africa, fourth seed Murray restored British pride with a crushing win on Centre Court to set up a last eight clash with France’s Jo-Wilfried Tsonga.
Murray has yet to drop a set in four matches at the All England Club this year and the Scot looks in his best form for months after some poor results heading into the tournament.
The third seed, Serbia’s Novak Djokovic, also made it through as he clinched a 7-5, 6-4, 3-6, 6-4 win over in-form Australian Lleyton Hewitt.
Djokovic admitted he had prepared himself for a gruelling match because he knew Hewitt, the 15th seed here, would be tough to overcome on grass.
"We both expected a long and difficult match. We played a long match here three years ago and it was something similar this time," Djokovic said.
"It could have gone either way but I played the right shots at the right time."
Hewitt, the 2002 Wimbledon champion, added: "When you lose any Grand Slam, you’re disappointed. But there are a lot of positives to take out of the last month so I’ve got to try and look at those as much as possible."
Swedish sixth seed Soderling, beaten in the French Open final recently, also moved into the last eight after defeating Spanish ninth seed David Ferrer 6-2, 5-7, 6-2, 3-6, 7-5.
In an all-French clash, 10th seed Tsonga beat 32nd seed Julien Benneteau 6-1, 6-4, 3-6, 6-1.