He's won four Bundesliga titles, lifted the FIFA World Cup, pledged one per cent of his wages to charity, modelled for Hugo Boss and now Mats Hummels is stepping into the world of custom football boot design. Well, not quite...

Eagle-eyed viewers among you may have spotted the 28-year-old sporting a rather unusual pair of kicks in Bayern Munich's 3-1 win over Borussia Dortmund in Der Klassiker on Saturday. Fans were left scratching their heads at the sight of meticulously carved holes in the toe of each boot, but there was method to the Bayern defender's madness.

Coming to a store near you: Hummels' custom Adidas ACE 17.1 Primeknits.

"Both toes are a bit injured at the moment," Hummels revealed. "It helps relieve the pressure. Maybe they will develop a new model."

The Germany international's performance wasn't impeded in any case as the defending champions cruised to a seventh successive win in all competitions to move four points clear at the Bundesliga summit.

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