London: Eight-time champion Roger Federer was sensationally knocked out of Wimbledon on Wednesday by South African giant Kevin Anderson while Rafael Nadal edged Juan Martin del Potro in a Centre Court epic and will meet Novak Djokovic in the semi-finals.

Defending champion Federer lost a Court One thriller, 2-6, 6-7 (5/7), 7-5, 6-4, 13-11 as 32-year-old Anderson became the first South African in the Wimbledon semi-finals since Kevin Curren in 1983.

Eighth seed Anderson will play American ninth seed John Isner on Friday for a place in Sunday’s final.

Three-time champion Novak Djokovic, meanwhile, reached his first semi-final at the majors in more than two years by seeing off Japan’s Kei Nishikori 6-3, 3-6, 6-2, 6-2.

The 12-time Slam champion will face old rival and world number one Nadal who saw off Del Potro 7-5, 6-7 (7/9), 4-6, 6-4, 6-4 after four hours and 48 minutes on Centre Court to reach his sixth Wimbledon semi-final and 28th at the majors.