Manchester United's defensive crisis seemingly got even worse after a 2-1 defeat at St. James' Park. Concerns are now growing over Noussair Mazraoui after video footage emerged showing the defender limping as he left the stadium.

The Africa Cup of Nations is the biggest event for the continent's football outside of the World Cup, but for clubs, especially ones in the Premier League, it can create a major headache. This time around, the next month could be a particularly painful period for Manchester United, as the tournament will deprive them of three of their usual starting XI in Noussair Mazraoui, Bryan Mbeumo and Amad Diallo.

Manchester United reportedly complained to FIFA after Morocco refused to allow Noussair Mazraoui to play in the club's Premier League game against Bournemouth. The Red Devils believed that the defender should have been eligible under the Africa Cup of Nations release arrangements. FIFA’s regulations state that players selected for AFCON squads must be released seven days before their nation’s opening fixture, with the release period beginning on December 15 - the day of the Bournemouth clash.

Ruben Amorim is reportedly ready to finally change tack at Manchester United and move away from his much-maligned 3-4-3 system. The Portuguese is being backed into a corner as Bryan Mbeumo, Amad and Noussair Mazraoui prepare to head off on Africa Cup of Nations duty. Their absence could lead to the Red Devils reverting to a back-four system.