London (AFP) - Kenya's Geoffrey Mutai has vowed to finally add the London Marathon title to his honours on Sunday, while three-time winner Paula Radcliffe prepares to bid a tearful farewell to the event.Radcliffe's last appearance in the race that established her as one of the finest female marathon runners of all time will be the main focus for British fans.But the battle for supremacy in the men's competition will provide a high-quality distraction from Radcliffe's emotional send-off.Mutai has crossed the finish line in first place in the Boston, Berlin and New York Marathons, but he has been unable to emulate those triumphs on the streets of London.In 2013 he dropped out with a hamstring problem at the 30-kilometre mark, while last year he was short of form and had to settle for sixth place.To end his frustrating wait for a London victory, the 33-year-old will have to see off a star-studded field, including compatriots Wilson Kipsang, the defending London champion, and world record holder Dennis Kimetto."I have won in Boston, Berlin and New York, but the win I still want is this one," Mutai said."The fact that I have not done well here before is my main motivation now.