 Shepherd signed with the senior Celtic side in August 1983 and debuted at Parkhead in a 2-1 Scottish Cup victory over Queen's Park on 15 February 1986, providing assists for both the goals in that game for Brian McClair and Roy Aitken.He was sent off in the 1986 Scottish League Cup Final when the referee assumed he had been struck by Shepherd from behind.When the referee accepted that he had been hit by a coin and not by Shepherd, he allowed Shepherd to remain on the field.