7. Michael Essien – 2005
The 30-year-old’s arrival at the club was one of the most drawn out transfer saga’s there there had been up until that point and he had cost the Special One a whopping £24m – a fee that made him the club’s most expensive signing.
However, he would quickly go on to repay the faith shown in him by the manager by becoming one of the most powerful and feared midfielders in the world. Mourinho likes him so much that he even took him on loan to Real Madrid last term and will be glad that they can continue their relationship in London.