Sixteen-time Grand Slam winner Roger Federer could slump to his lowest ranking in more than eight years if Andy Murray wins the Shanghai Masters, ATP officials confirmed on Saturday. The Swiss great is missing from Shanghai and will therefore garner no points, at the same time losing all his 600 points earned for finishing as runner-up last year in the 12-month rolling rankings. Murray, on the other hand, would earn 1,000 points should he defend his Shanghai Masters crown on Sunday, which would mean he would leapfrog Federer into third place in Monday's new weekly rankings. The last time Federer was ranked lower than number three was way back in June 2003, the month before he won his first Grand Slam at Wimbledon, which signalled the start of a period of astonishing dominance in the sport. He held the number one position for a record 237 consecutive weeks. A win for the current British world number four would see Federer slip behind Novak Djokovic, Rafael Nadal and Murray, facing the extra pressure of points to defend as the reigning champion at the ATP World Tour Finals. Such a slide down the rankings for Federer would give ammunition to those who believe the Swiss, at 30, has seen his best days, with 2011 his first year without a Grand Slam since 2002. He has won just one title this year, in Doha.