Nicolas Anelka
Controversial it may be, but Nicolas Anelka never fulfilled the full potential that his early performances at Arsenal suggested he had – and that has to go, at least partly, down to his time at Real Madrid.
The Spaniards paid a huge fee to land him from Highbury, but Anelka was largely woeful in Spain and went on to have a career largely as a well paid journeyman, although his time at Chelsea was a big success.
The less said about his most recent spells, with West Bromwich Albion and Mumbai City, the better.