#10. Kaka – £56m
The poster boy of Carlo Ancelotti’s famous Milan side of the mid 2000’s, Kaka was a globally adored superstar before his transfer to the Spanish giants Real Madrid. Winning the Ballon D’or in 2007 after leading Milan to a stunning Champions League victory, Kaka was one of the most sought after footballers in the world, and Real Madrid, true to their Galacticos theory, promptly jumped in to finalize a mega deal. The Brazilian was expected to light up the capital, however, primarily due to an unfortunate string of injuries, he could simply not adapt to the Spanish league and was largely considered a flop before returning to Milan on loan.