Rafael Nadal's charge towards a third Wimbledon title came to a juddering halt in the fourth round when he was sensationally beaten by 19-year-old Australian wildcard Nick Kyrgios 7-6(5) 5-7 7-6(5) 6-3.
Ranked 144th in the world, Kyrgios fired down 37 aces and played a fearless brand of tennis to topple the world number one following two hours and 58 minutes of exhilarating action.
It was the first time since 1992 a man ranked outside the top 100 had beaten a world number one.
Former world junior number one Kyrgios is competing at his first Wimbledon and will next play Canadian eighth seed Milos Raonic for a place in the semi-finals.
No problem for Federer
With a dominant display of grass-court tennis, Roger Federer kept up his bid for a record eighth Wimbledon title by beating Tommy Robredo in straight sets to reach the quarter-finals at the All England Club for the 12th time.
The fourth-seeded Federer, who has not dropped a set in the entire tournament, overwhelmed the Spaniard 6-1, 6-1, 6-4 in just over 90 minutes on number one Court.
He hit 11 aces, faced only one break point and broke four times in a performance that showed he remains a real contender at the age of 32.
"It's really nice the way I'm playing," Federer said. "I'm serving well, moving well, returning all right, so all the things are happening that need to be happening to go deep in this tournament again.''
The win avenged Federer's straight-set loss to Robredo in their last meeting in the fourth round of the U.S. Open. Apart from that defeat, Federer has won all of his 11 matches against the Spaniard.
Federer's win set up an all-Swiss duel with Australian Open champion Stan Wawrinka, who beat Feliciano Lopez 7-6 (5), 7-6 (7), 6-3 to make it to the Wimbledon quarter-finals for the first time.