7) Mats Hummels (Borussia Dortmund)
One of the best defenders in the world, Borussia Dortmund will do well to cope if Mats Hummels does end up joining Manchester United this summer.
8) Marco Reus (Borussia Dortmund)
Another important Dortmund star, Marco Reus is wanted by the likes of Arsenal, Chelsea and Real Madrid this summer and will prove very hard to replace as Dortmund continue to move backwards.