Man United transfer spending to reach £200m in January as van Gaal eyes £50m duo

2) Mats Hummels (Borussia Dortmund)

Valued at roughly £20m, Borussia Dortmund defender Mats Hummels is undoubtedly one of the best centre-backs in the world, and one who would make a useful signing for this United side as they continue to struggle defensively. With van Gaal insisting on playing three at the back, more signings are needed to upgrade on the likes of Jonny Evans and Chris Smalling, with other summer targets such as Mehdi Benatia slipping through the net.

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