6) Adrian Mutu (Chelsea)
The striker was tipped to be a huge success at Chelsea, but managed just 27 Premier League appearances and six goals before being sacked over a breach of contract. It was later confirmed that he had failed a drugs test for cocaine.
5) Fernando Morientes (Liverpool)
The ex-Spanish international scored goal at a ratio of less than one in three at Real Madrid, but managed just eight goals in 41 Premier League games for the Reds. He left for Valencia after just two seasons, with his career coming to an end a couple of years later.