Isner bows out with injury

London - Wimbledon marathon man John Isner was forced to retire after two games of his second round match against Frenchman Adrian Mannarino with a knee injury on Wednesday.

American Isner, who wrote his name into Wimbledon folklore when he played in the longest match in professional tennis in 2010 against Nicolas Mahut, pulled up while serving at 1-1 in the first set.

The 18th seed received extensive treatment on Court Three and attempted to battle through the pain barrier, but had to throw in the towel.

Isner is famous for his part in a record 11-hour-five-minute first round match at Wimbledon against Frenchman Mahut which he won 70-68 in the fifth set.