Switching teams can be difficult for a player in modern-day soccer (football), but it's even harder when you transfer to your city rivals.
On countless occasions in the past, great players have made cross-town moves, switches that made them instant villains in the eyes of their former fans. These transfers are conducted for money, for more playing time, or for fame (and other less common reasons).
Here's a list of five players who transferred from one side of the city to the other:
(Note: this article focuses on more recent switches)