Due to the good form of Packie Bonner at Celtic, Marshall was in and out of the first-team and was eventually sent out on loan for first-team experience to St Mirren and English club Stoke City, where he played thirteen times in the 1993–94 season. It was not until Tommy Burns was appointed Celtic's manager at the start of the 1994–95 season that Marshall was the regular first choice goalkeeper. However, that year he was criticised for an error which led to a goal in a shock loss to Raith Rovers in the 1994 Scottish League Cup Final, while Bonner took the jersey for the 1995 Scottish Cup Final victory, Marshall collecting a medal as an unused substitute.