The rivalry between Rangers and Celtic is considered to be the fiercest in world football by many supporters not just in Scotland but from all corners of the globe.
Throughout the years there have been a handful of players who have either represented or been on the books at one point for both clubs. Even fewer have played for both in the Old Firm derby and no player has ever transferred directly from one club to the other.
Here are 12 players who have either played for or been on the books at both Celtic and Rangers in the past 30 years: