Next month’s world heavyweight title rematch between champion Tyson Fury and Ukrainian Vladimir Klitschko was called off on Friday for a second time with the Briton ruled “medically unfit”. The fight was due to be held on Oct. 29 in Manchester, having been originally postponed in July when Fury suffered an ankle injury. “Tyson has this week been declared medically unfit to fight,” his promoters Hennessy Sports said in a statement without elaborating.