3) Marcos Rojo (Sporting Lisbon)
A World Cup finalist with Argentina after their penalty shoot-out success over the Netherlands yesterday, Marcos Rojo‘s reputation is growing fast this summer. The Sporting Lisbon defender, who can play either as a centre-back or left-back, would be a great signing for Chelsea as they look for options in both of those positions. Still only 24 years old, Rojo has his best years ahead of him, and has been identified as a top prospect by big clubs such as Arsenal and Liverpool as well as Chelsea this summer. The Argentine full-back may not have been the cheapest option, but he certainly looks a good alternative to Luis as a long-term option at left-back for the Blues.