A cook by trade, John Spellacy spent the 1896-97 season with the Saints, mainly as the Reserves’ centre-forward.

His one first-team appearance was in an FA Cup-tie. Reaching the Second Round Proper for the first time, the Saints were held to a draw at The Dell by Newton Heath, the club that would shortly become Manchester United. Obliged to replay in Manchester four days later, St Mary’s needed to replace the injured Chippy Naughton with Spellacy. Saints went out to a 3-1 scoreline. After which, John had to settle, that season, for being the Reserves’ top-scorer and for representing Hampshire v Dorset. He moved to Cowes in the summer and was part of their aborted experience of Southern League football in 1899-1900.