As most football fans will know, Scotland's biggest city is divided into two camps: one favors Celtic, the other favors Rangers. I'm sure fiercer footballing rivalries exist, but there can't be many. Because whereas most rivalries at least confine themselves to football, in Glasgow there's an added dimension of sectarianism to the mutual envy and hatred. Celtic, founded for and by Irish immigrants, is the team of Catholic Glasgow, and Rangers that of the Protestants. The ferociousness of the rivalry meant a player switching between the two clubs was completely unthinkable.
Yet switching was exactly what Maurice "Mo" Johnston -indirectly- did in the summer of 1989. The forward had played for Celtic for three seasons, between 1984 and 1987, scoring 52 goals in 99 games. Johnston had won the cup with the Catholic club in 1985 and had added the league title a season later. When the Scottish international decided to return to Scotland after a stint playing in France, Celtic was the most obvious destination. The fact that he signed for Rangers instead, came as a bolt from the blue.