Rafael Nadal was sent tumbling out of Wimbledon by Australian teenager Nick Kyrgios on Tuesday as the Spaniard suffered another All England Club meltdown which in turn opened the title door for Roger Federer.
World number 144 Kyrgios, just 19 and making his tournament debut, bundled out the 14-time Grand Slam title winner in the fourth round with a fearless 7-6 (7/5), 5-7, 7-6 (7/5), 6-3 victory.
The defeat boosted Federer's hopes of an eighth title as the Swiss star was seeded to meet Nadal in the semi-finals.
The seven-time champion had earlier booked a place in the quarter-finals for the 12th time with a 6-1, 6-4, 6-4 win over Tommy Robredo.
He will tackle Australian Open champion and Swiss compatriot Stan Wawrinka, the fifth seed, who made his first last-eight date at the All England Club at the 10th attempt by seeing off Spain's Feliciano Lopez 7-6 (7/5), 7-6 (9/7), 6-3.
But Kyrgios was the talk of the town as he became the first wildcard in 10 years to make the quarter-finals.
He is also the first player ranked outside the top 100 to defeat a world number one since Andrei Olhovskiy stunned Jim Courier in the Wimbledon third round in 1992.
It was a performance of brutal inventiveness and uninhibited bludgeoning from a man who had had to save nine match points in his second round against Richard Gasquet and his reward is a clash with Canada's Milos Raonic for a place in the semi-finals.
For Nadal, the 2008 and 2010 champion, it was a third successive disappointing Wimbledon with Tuesday's loss following a first round exit last year and a second round defeat in 2012.
All three defeats were against players outside the top 100.
But he cannot argue with the statistics of his Centre Court demolition which showed Kyrgios firing 37 aces and 70 winners.
"I played some extraordinary tennis. I was struggling a little bit on return but I worked my way into it and I got that break in the fourth set. I served at a really good level all throughout the match so I was really happy," said Kyrgios.
He said he always believed he could cause a sensation regardless of the status of Nadal who had arrived at Wimbledon having wrapped up a ninth French Open title.
"You've got to believe that you can win the match from the start and I definitely thought that. I'm playing some unbelievable tennis on the grass."
Nadal said defeat was hard to take as he only lost serve once.
"On a surface like this when he serves and hits every ball strongly, you are in trouble," said the second seed.
"I didn't think I played that badly. I was better in the first and third sets but I wasn't able to convert my opportunities. He was better at the other times. He did the things he needed to do to win on grass better than me."
Nadal added: "I congratulate him. For me? The beach."
Federer will start Wednesday's quarter-final against Wawrinka as overwhelming favourite having a 13-2 record over his 2008 Olympic Games gold medal partner.
But Wawrinka won their last encounter on clay at the Monte Carlo Masters final in April and the two have never met on grass.
Federer allowed fellow 32-year-old Robredo just three points off his serve in the first set and then none at all in the second with the 17-time Grand Slam title winner claiming 20 out of 20 points on service.
In all, Robredo won just 14 points on the Federer serve as the Swiss star went level with Boris Becker in joint second place for most match wins at the tournament on 71.
Federer finished with 11 aces and 41 winners and has still to drop a set in the tournament in marked contrast to 12 months ago when he was knocked out in the second round.
Eighth-seeded Raonic celebrated his national day in style by becoming the first Canadian man in more than a century to reach the quarter-finals as he knocked out Kei Nishikori.
Raonic beat the 10th-seeded Japanese 4-6, 6-1, 7-6 (7/4), 6-3, firing 35 aces and 66 winners. - AFP