NEW YORK - Andy Murray hobbled out of the U.S. Open Sunday, beaten 6-7 7-6 6-3 6-3 in the third round by Switzerland's Stanislas Wawrinka after his ailing body let him down.
Struggling to run at full speed after requiring treatment to his legs, elbow and neck, a clearly frustrated Murray appeared powerless to stop Wawrinka, who was battling his own injury problems but still played superbly, from pulling off the biggest upset of the championship.
"I was struggling physically and I got frustrated with that," Murray said.
"Maybe I felt like my chance of doing well here was slipping away. I've worked very hard to give myself a chance of winning tournaments.
"It happens to everyone in life at different points."
It was another disappointment for the Scotsman, who arrived at Flushing Meadows seeded fourth, in great form, and holding genuine hopes of ending Britain's 74-year wait for a men's grand slam singles champion.
"I'm very disappointed, obviously, but I think I've been more disappointed," Murray said.
"In other Grand Slams, when you get closer to winning the tournament, it becomes a lot harder to take."
Wawrinka, seeded 25th, advanced to play American Sam Querrey in the fourth round although the big winner could well be Rafa Nadal, who was drawn to face Murray in the semi-finals.
Nadal, playing before Murray's defeat, had sent an ominous warning to his rivals about his intentions to win the U.S. Open and complete his collection of grand slam titles but Murray was looming as one of his biggest obstacles.
The Spaniard, getting better with each match on the back of a new and improved serve, overpowered France's Gilles Simon 6-4 6-4 6-2 to steam into the fourth round without dropping a single service game in three matches.
"It was important not to lose without dropping a set," Nadal said. "Every day I seem to play much better which is good for my confidence."
Venus advances
Venus Williams and Kim Clijsters passed their first real tests of the championship with flying colours to safely book their places in the women's quarter-finals.
The pair could hardly have been more impressive as they swept past tricky opponents to remain on course for a blockbuster semi-final showdown when the last grand slam of the season enters the second week.
Williams, the champion at Flushing Meadows in 2000 and 2001, defeated Israeli 16th seed Shahar Peer 7-6 6-3 in an ideal test for the more difficult matches ahead of her.
"It's always good to have a tougher match, a kind of a match where you have to challenge yourself against your opponent and the conditions," Williams said.
"We always have had very competitive matches, so I know it's not going to be something I just walk through when I play against her.
"I have to stay focussed and ready to take every point or else she will. It was a good challenge."
Clijsters, who won the title in 2005 and again last year, thrashed Serbia's former world number one Ana Ivanovic 6-2 6-1 in just under an hour. Like Nadal and Williams, she is yet to drop a set in the championship.
"You always want to do well at tournaments where you've done well, and obviously, the U.S. Open is a special tournament for me," Clijsters said.
"Tennis wise, I feel that I've been improving every match. I want to try and keep it going."
Schiavone cruises
Italy's Francesca Schiavone, brimming with confidence after winning her maiden grand slam title at this year's French Open, also cruised through to the last eight, beating Russia's Anastasia Pavlyuchenkova 6-3 6-0.
Schiavone will play Williams in Tuesday's quarter-finals while Clijsters will face the winner of Sunday's late match between Australia's Samantha Stosur and Elena Dementieva of Russia.
"I feel better than when I was in French Open, but just because I know how to do it and how to win a match like this," Schiavone said.
"So I'm very curious, I'm interested to see write a new history."
Spain are already assured of at least one men's semi-finalist after Fernando Verdasco, David Ferrer and Felciano Lopez joined their countryman Nadal in the same section of the draw.
Nadal will face Lopez next with the winner to play either Ferrer or Verdasco.
Another two Spaniards, Albert Montanes and Tommy Robredo, are also through to the last 16, giving Spain a total of six, easily the most by any one country this year.
"It's always nice to see all the Spanish winning and being in the last rounds," said Verdasco, who advanced with a four set win over Argentine David Nalbandian.
