Reilly learnt his goalkeeping skills while playing with local Aberdeenshire Junior sides Parkvale, in his hometown of Stonehaven, and Inverurie Loco Works, prior to moving to the reserve team of Hibernian.
He made only two first appearances in the Scottish Football League[1] before moving to American club Washington Whips in 1968.
After showing immense talent during his debut season he was drafted into the Australia squad for a world tour.
[1] His transfer from St George Saints to Melbourne Hakoah in early 1972 was a then record fee for a goalkeeper of $6,000.
Reilly continued to represent Australia and was selected for their 1974 FIFA World Cup squad.