He accompanied Johnny Giles back to Ireland to join Shamrock Rovers F.C. in 1977. Giles wanted to make the club Ireland's first full-time professional club, and hoped to make Rovers into a force in European football by developing talented young players at home who would otherwise go to clubs in England. Dunphy was originally intended to be in charge of youth development. However, despite an FAI Cup winners medal in 1978 (his only medal in senior football) and two appearances in the UEFA Cup Winners' Cup, Dunphy became disillusioned with the Irish game and dropped out of football altogether to concentrate on a career in journalism.