5. Juan Mata
Juan Mata was Chelsea’s Player of the Season for two years in a row, but after Jose Mourinho arrived, his form drastically dropped, as did his importance at Stamford Bridge.
Mourinho didn’t like Mata‘s style of play and criticised him for his defensive efforts, and by January, he was shipped out to Manchester United for £37million.
Chelsea fans were gutted to see the Spaniard leave and some are still furious that the playmaker was allowed to leave, especially after he joined a fierce-rival.
