Stanislas Wawrinka sensationally ended Novak Djokovic's 25-match winning run at the Australian Open as he finally got the better of the defending champion.
Twelve months ago Djokovic won a fourth-round clash against Wawrinka 12-10 in the fifth set in Melbourne while the outcome was the same when they met in the last four at the US Open.
But this time, as the clock registered four hours, Djokovic placed a volley wide on Wawrinka's first match point to give the Swiss a 2-6 6-4 6-2 3-6 9-7 victory.
Djokovic was bidding to become the first man since Roy Emerson to win four straight Australian Open titles, and he had not lost a match since the US Open final in September.
Wawrinka said: "Last year it was really tough but this year I came back, it's a new year. I did not start well, I was not feeling great on the court. I tried everything. He's an amazing champion and he never gives up but I'm really, really, really happy."
Djokovic breezed through the first set on Rod Laver Arena, but Wawrinka cut out the errors and found his form during the second set, ripping his one-handed backhand, and it paid dividends in the seventh game when he landed one on the line to break the Djokovic serve.
He nervelessly served it out, and in the third set the champion simply could not live with his opponent.
One thing that can be guaranteed from Djokovic, though, is a fight, and he let out an almighty roar when he broke the Wawrinka serve to lead 5-3 in the fourth set.
The Swiss had been 40-0 up but Djokovic somehow stretched to arc a return winner into the corner to set up break point and took it when Wawrinka blazed a forehand well out.
Wawrinka had two chances to break back but netted a forehand on the first and Djokovic served an ace on the second, while a second ace on set point drew another roar.
It seemed Djokovic had done the hard work when he broke again for 2-1 in the deciding set but he then threw in a poor game to hand the initiative straight back.
Djokovic had more chances in the fifth and seventh games but Wawrinka showed exceptional mental strength, and no little skill, to hold his opponent off.
There was more drama in the 11th game when, with Wawrinka leading 40-15, it began to spit with rain and there was a short delay.
It was no problem for the eighth seed, who finished off the game with an ace, and on they went.
Wawrinka was struggling a little with cramp but it was he who looked the more confident and eager to attack, and when Djokovic missed a backhand he had his first match point.
The Serbian looked set to save it as he positioned himself for a simple volley but as soon as he hit it the crowd knew Wawrinka had won the match.
In the last four he will face Tomas Berdych, who ousted David Ferrer to reach the semi-finals in Melbourne for the first time.
Berdych joined Djokovic, Rafael Nadal, Roger Federer and Andy Murray in completing his set of grand slam semi-finals with victory over Ferrer.
Ever tried. Ever failed. No matter. Try again. Fail again. Fail better. – Dubliner Samuel Beckett was the man to pen the words which inspired Stanislas Wawrinka’s ink
The Czech was playing in the quarter-finals in Melbourne for the fourth straight year and this time he came out on top, winning 6-1 6-4 2-6 6-4.
The main talking point about his run in the tournament until this match had been his blue and white striped shirt, so comfortable had his progress been.
It looked like being another walk in the park here until Berdych's level dropped in the third set and Ferrer roared back.
The Spaniard seemed to have the momentum in the fourth, too, but Berdych hung on and then claimed the crucial break of serve.
The seventh seed narrowly missed a forehand on his first match point and then had to save a Ferrer break point when he served for it, but on his second chance the Czech clinched victory.