By Dan Marsh Manchester United will miss out on a whopping £10million if they fail to qualify for the Champions League due to a clause in their lucrative contract with sponsors Adidas. The Red Devils may have fallen on hard times off the pitch in recent years, but their commercial appeal certainly hasn’t waned. It was announced last year that they had agreed to extend their sponsorship agreement with Adidas in a deal worth £900m over 10 years, tying them to the German sportswear giants until 2035. While that deal is significant, it has now emerged that some payments are linked to on-field succ…