US Open: Spectators stunned as Federer suffers shock loss

Roger Federer suffered a shock loss to Tommy Robredo at the US Open on Monday, ruining the chance of meeting Rafael Nadal at the only Grand Slam where the two greats have never played each other.

-Vinci storms into US Open quarters before rain halts play

In the biggest upset of the tournament, Robredo demolished a badly out-of-sorts Federer 7-6(3), 6-3, 6-4 in the fourth round, marking the first time in a decade the Swiss master has fallen before the quarter-finals at Flushing Meadows.

His straight-sets defeat left the New York crowd stunned by what they had witnessed in a match that was moved from Arthur Ashe Stadium to the smaller Louis Armstrong Stadium following a five-hour rain delay.

"I feel like I beat myself, without taking any credit away from Tommy," Federer said. 

Robredo will now play Nadal in the quarter-finals, the long-awaited clash between Federer and Nadal in the Big Apple put on hold for at least another year.

"I kind of self destructed, which is pretty disappointing.

"When things came to the crunch I just couldn't do it."

Spain's Rafael Nadal lost a set for the first time at this year's US Open on Monday but recovered quickly to safely book his place in the quarter-finals, albeit against an unexpected opponent.

Nadal gave his supporters at Flushing Meadows a brief heart flutter when he lost the opening set to Philipp Kohlschreiber but rebounded to beat the German 6-7(4), 6-4, 6-3, 6-1.

The 2010 US Open champion, Nadal's next match is against his countryman Tommy Robredo, who pulled off a shock straight-sets win over Roger Federer that ended the prospect of a first US Open showdown between the two greatest players of their generation.

Nadal was in great form in the lead-up to the last major of the year, winning Masters titles in Montreal and Cincinnati, and has continued his red-hot streak at Flushing Meadows.

After struggling with knee problems for years, the world number two has made some slight alterations to his game to help him cope with the demanding hardcourts in North America.

The lefthander has taken some of the speed off his serve to focus more on his accuracy. Against Kohlschreiber, Nadal hit just three aces, but faced only one break point on his serve, which he successfully fought off.

"It was very, very tough conditions," Nadal said courtside.

"Very humid, I sweat too much. The opponent was great and I am lucky to go through.

"Physically it was a very tough match but with my serve, I felt comfortable."

Nadal said Robredo would be in a dangerous mood after beating Federer.

"To beat Roger at the US Open is amazing for him," Nadal said. "He will be confident and I hope to be ready for that."

Federer's unforeseen loss to a player he had beaten in all of their 10 previous meetings overshadowed a remarkable turnaround by Daniela Hantuchova, who advanced to the quarter-finals for the first time in more than a decade.

The 30-year-old Hantuchova had not reached the last eight in New York since she was a teenager in 2002 but made up for lost time with a 6-3 5-7 6-2 victory over American wildcard Alison Riske.

"I guess the best things happen when you don't expect them," said Hantuchova, now ranked 48th in the world.

David Ferrer battled his way into the quarter-finals of the US Open on Monday with a hard-fought 7-6(2), 3-6, 7-5, 7-6(3) win over Serbia's Janko Tipsarevic.

Ferrer, seeded fourth, retained his composure after dropping the second set to win a gruelling slugfest that took nearly four hours to complete after being moved to one of the smaller showcourts because of a lengthy rain delay.

The tenacious Ferrer became the second Spaniard to reach the men's quarter-finals on Monday, joining Tommy Robredo who had upset former World No 1 Roger Federer.

Ferrer's next opponent will be either French eighth seed Richard Gasquet or Canada's Milos Raonic.

Although Ferrer has not won a Grand Slam, the 31-year-old baseliner has proven himself to be one of the most consistent players on tour.

He has reached the quarter-finals or better at each of the last eight majors and was a finalist at the French Open in June.

Hantuchova will have to wait another day to learn who her opponent will be after the fourth round match between Victoria Azarenka and Ana Ivanovic was postponed until Tuesday because of the foul weather.

New York's fickle weather has been a major talking point at the US Open for years with each of the last five men's finals spilling into a third week because of rain delays.

For years, US Tennis Association officials balked at the idea of building a roof because of the enormous cost of covering Arthur Ashe Stadium, the largest tennis stadium in the world.

But they have finally relented, announcing two weeks ago that they would commence a massive renovation program, which would include a roof, by 2016 at the earliest.