Tomas Berdych pulled off the biggest win of his career as defending champion Roger Federer crashed out of Wimbledon.
Federer, who has won the men's singles title in six of the last seven years, became the latest casualty in a tournament of shocks as he went down 6-4 3-6 6-1 6-4 to the world number 13 on a stunned Centre Court.
The result was greeted with widespread disbelief as the Swiss ace joined last year's runner-up Andy Roddick and women's second seed Venus Williams on the wayside.
Berdych, who had lost eight of his previous 10 meetings with Federer, becomes the first Czech to reach the semi-finals of the Wimbledon men's singles since Ivan Lendl 20 years ago and is aiming to become the first winner from his country since Jan Kodes in 1973.
Standing in his way in Friday's semi-finals will be third seed Novak Djokovic, who has beaten him in both their previous meetings.
The 24-year-old Czech is through to his first Wimbledon semi-final to match his achievement in the French Open at Roland Garros earlier this month which gave him the self-belief he needed coming into the Championships.
"It was really big for my confidence," Berdych said. "That was my first grand slam semi-final and it made me quite hungry for my next matches."
Federer had little answer to the powerful serving of Berdych, who averaged 129mph with his first serve and produced a series of spectacular forehand winners to stun a bewildered champion.
Federer's air of invincibility had been undermined when he failed to reach the semi-finals of the French Open and he had lived dangerously in the first week of Wimbledon.
He dropped three sets in his first two matches, and, although he got his title defence back on track with straight-sets wins over Arnaud Clement and Jurgen Melzer to reach the last eight, there were signs from the opening game that all was not well with the six-time champion.
Berdych, who beat Federer in their last meeting in Miami earlier this year, caused problems with his sweet forehand and drew first blood when his opponent hit a backhand long on the first break point of the match in the seventh game.
The world number 13 consolidated to go 5-3 up and served out to close the opening set after 34 minutes.
It looked to be the wake-up call the champion clearly needed as he roared back in typical fashion in the second set, breaking his opponent for the first time in the second game.
When the 6ft 5in Berdych failed to clinically put away an easy forehand at the net, the Swiss ace punished him with a rasping passing shot.
Berdych's first serve deserted him in the eighth game of the second set in which he had to save a set point but he could not achieve a second break against Federer, who served out to take the second set 6-3 and level the match.
Berdych produced a superb half-volley at the start of the third set in a rare foray to the net but it was his fierce forehand that brought him rich rewards in the second game.
A forehand winner gave him only a second break point which he seized when Federer put a backhand into the net.
Federer's accuracy deserted him in the sixth game in which Berdych went a double break up thanks to a clinical backhand down the line.
Berdych, who has never lost a five-set match at Wimbledon, served out to take the set 6-1 and, brimming with confidence, he showed no sign of relaxing his grip on the match.
He wobbled in the sixth game of the fourth set when he produced successive double faults, this after serving only four in the first two hours, but redeemed himself largely with his big first serve, to save four break points.
Another pivotal moment came in the next game in which Federer lost direction with both forehand and backhand to drop his serve, despite producing a 127mph ace, his fastest serve of the match.
Berdych held his serve to go 5-3 in front and, although Federer managed to save one match point, he could do little to prevent the Czech number one fittingly hitting the winner with a trademark forehand.
Federer said: "I didn't think I played poorly, but I think he went after it.
"I know Berdych. I've played him 10 times before. He's been able to perform more consistently in the last year or so.
"I wasn't able to defend well enough or come up with good stuff when I had to, so it's disappointing."
He revealed injuries have been a factor in his below-par performances this fortnight.
"I'm unhappy with the way I'm playing. I couldn't play the way I wanted to play. I am struggling with a little bit of a back and a leg issue. That just doesn't quite allow me to play the way I would like to play," Federer said.
"So it's frustrating, to say the least. I'm looking forward to some rest anyway.
"You can't concentrate on each and every point because you do feel the pain sometimes. And then you tend to play differently than the way you want to play.
"Under the circumstances I think I played a decent match. But I've been feeling bad for the last two, three matches now. It's just not good and healthy to play under these kind of conditions.
"So if there's anything good about this it's that I'm going to get some rest."