Manchester United have reportedly been left 'stunned' by Paul Pogba's claim that question marks still lingered over his future at Old Trafford.

The French midfielder told reporters in June that he wanted a "new challenge" three years on from returning to United from Juventus for £89m.

Speaking after United's 4-0 win over Chelsea on Sunday, Pogba admitted that there remained "question marks" about his future at the club.

According to The Mirror, United were left deeply concerned by the 26-year-old's comments after the game.

The Red Devils received keen interest from Real Madrid for the signature of Pogba but refused to budge on their £170m valuation of the player.

Club president Florentino Perez reportedly offered a player-plus-cash deal involving James Rodriguez and £27.4m for Pogba, but this bid was flatly rejected by United.