West Ham's move for Noussair Mazraoui has reportedly collapsed, leaving the door pen for Man United to swoop in.
The news broke on Thursday that the Hammers had agreed a £13.5m fee with Bayern Munich for the right back plus £3m in add-ons.
However, the deal has fallen apart as the two sides were unable to agree on terms.
Sky reporter Florian Plettenberg tweeted: 'Noussair Mazraoui deal with West Ham is OFF! no agreement on agent‘s side has been reached.
'Despite the agreement between the clubs and on player‘s side West Ham now have left the negotiations.