He turned professional in 1977, and started out on the Professional Golf Association Tour of Australasia. Riley came through the European Tour"s final qualifying school in 1984, but had to wait eleven years before winning his first tournament on the tour, the 1995 Scottish Open. He finished a career high 11th on the in 1995.
Riley represented Australia in the 1996 Alfred Dunhill Cup and the 1997 World Cup.
Since leaving the tour, Riley has worked for Sky Sports as an on course commentator on their European Tour coverage. European Tour wins (2) 1995 Scottish Open Professional Golf Association Tour of Australasia (4) Other wins.