LONDON - Wimbledon turned tennis upside down Wednesday when Novak Djokovic was named top seed above world number one Rafael Nadal while defending champion Andy Murray was seeded three over seven-time winner Roger Federer.

The All England Club awarded top billing to 27-year-old Djokovic, the 2011 champion and 2013 runner-up, by using its controversial grasscourt weighting system in deciding its seeds instead of sticking by the ATP world rankings. French Open champion Nadal, the 2008 and 2010 Wimbledon winner, is relegated from his world number one ranking to the second seeding after losing in the first round in 2013 and second round 12 months earlier.

Murray, who became Britain's first men's champion since Fred Perry in 1936 when he swept past Djokovic in last year's final, has been elevated to the third seeding despite a world ranking of five. Federer, a shock second round loser to Sergei Stakhovsky in 2013 and who won the last of his seven titles in 2012, was handed the fourth seeding in line with his current ranking. World number three Stan Wawrinka has never got beyond the fourth round at Wimbledon and has lost in the first round in 2012 and 2013.

That modest form is reflected in his seeding of five. "Wimbledon, they do what they want. For me it's fine," said Australian Open champion Wawrinka when asked about the seeding system when he was at Queen's Club last week where he made the semi-finals. "I knew that with my past two years on grass I didn't have any results, so for sure my ranking will drop a little bit for the seedings. "At the end of the day, it doesn't change much. You have to play well. You have to start the tournament well if you want to go far, and that's simple." Wawrinka's build-up to the tournament has been hit by illness after he developed a fever following practice on Monday. The 29-year-old is not expected to train again until Thursday.

The women's seedings follow the WTA world rankings with five-time champion Serena Williams the number one followed by China's Li Na, Simona Halep of Romainia in third and Poland's Agnieszka Radwanska taking fourth spot. Maria Sharapova, the champion at Wimbledon 10 years ago as a 17-year-old, is seeded five. This year's women's event is guaranteed a new champion after France's Marion Bartoli, the shock 2013 winner, retired from the sport soon after her lone Grand Slam triumph.