American heavyweight Charles Martin will be ready to take Anthony Joshua's place should the world champion pull out of his fight against Kubrat Pulev.
Joshua is scheduled to fight Pulev in either October or November this year.
There was concern, however, when Joshua was pictured at a Black Lives Matter protest in Watford wearing a knee brace.
Joshua was pictured wearing a knee brace last weekend at a Black Lives Matter protest
While Joshua's promoter, Eddie Hearn, has said the fight isn't under threat, Martin, who was knocked out by Joshua when they met at the O2 Arena in 2016, would be prepared to stand in at the last minute if he needed to.