regained the English heavyweight championship against Goss in a 21-round victory on 6 August 1866 between Purfleet, Essex, and Gravesend on the North bank of the Thames, twenty miles East of London. By one reliable account, the ring used was only sixteen feet square, eight square feet shorter than the regulation size. Mace was said to be suffering from a strained left foot or ankle. In a close physical matching, Goss was nearly the same height, and only a few pounds lighter, at around 158 pounds. Goss, though he had the vitality of a man nearly seven years younger, did not gain from the advantage, as Mace's experience, skill, and conditioning seemed to count for more than the wear he'd received from his years in the ring. Mace deftly avoided Goss's strong rushes with a shift of his shoulders or a bob of his head, showing great flexibility and speed. Mace could strike or counter quickly, particularly using his left, and often did so under Goss's defences, even in the early rounds where he scored early and with precision. Mace, in the 14th through 20th rounds, got the better of Goss, frequently striking his left eye with his right fist. At the end of the match in the 21st round, Mace remained strong, but Goss was groggy and weak. Mace was said to have very few injuries, but Goss had been battered around the "head, face, neck, and chest", with loosened teeth and badly battered eyes. In the final round, Goss's seconds threw up the sponge ending the fight when their boxer staggered in his attempt to land a blow on Mace, who defended himself by merely stepping aside. Bare-knuckle boxing was an outlawed sport and both boxers, trainers, and seconds were often liable for arrest and prosecution. In 1867, Mace was arrested on the night before his scheduled title defence against Ned O'Baldwin in Woodford Essex, by the Metropolitan Police. He was held over in court not to fight again, and the incident influenced him to seek his fortune in America. In 1869 he relocated to the United States where prizefighting was still flourishing. He toured with the celebrated American boxer John C. Heenan, giving exhibitions of glove boxing. World heavyweight champion, 1870 In what should be considered his most significant victory, on 10 May 1870, he defeated the English-born American boxer Tom Allen for a purse of $2500