 He performed this duty for Tom Tyne ("The Tailor") at Croydon on 1 July 1788 and at Horton Moor on 24 March 1790, having previously done so for a fighter called Savage who had taken on Jack Doyle at Stepney Fields on 22 November 1787.He also acted twice for Humphries, in his fights against Mendoza at Odiham on 9 January 1788, when Mendoza sprained his ankle on the slippery surface, and at Stilton on 9 May 1789.There was much controversy at the latter, with O'Hara reporting that this caused Mendoza's second, a Captain Brown, to call Johnson a blackguard; Johnson responded by threatening "to punch Brown into Eternity."