2) Mats Hummels
One of the best defenders in Europe, and now a World Cup winner with Germany, Mats Hummels may finally be on the move this summer after long being linked with some of the world’s biggest clubs. Manchester United are known to be big admirers of his as they chase new signings in defence, while Barcelona and Juventus have also been linked with him on several occasions. A rock-solid and intelligent centre-back, Borussia Dortmund won’t want to lose him after seeing so many other of their stars leave in recent times, but they will face an even tougher task holding onto him now after his fine performances on the biggest stage.