Gael Kakuta (Chelsea)
The Frenchman was involved in a controversial transfer to Chelsea in 2009. The Blues were banned from making signings for two transfer windows after being found guilty of inducing the player to break his contract at Lens to make the switch to Stamford Bridge. However, the Court of Arbitration for Sport lifted the ban after deciding Kakuta’s contract was invalid.
The effort to sign the winger really wasn’t worth it. He ended up playing just 16 games for the Blues as well as going out on loan to six different clubs. He eventually left for Sevilla in 2016 before having spells in China and France. Ironically, he is currently playing for Lens, on loan from Amiens.