The Premier League giants were humbled 4-0 at Anfield by Liverpool and were roundly criticised for the lack of fight, spirit and application on Merseyside.
Mejbri came on for the final ten minutes, launched into a few Liverpool players and got into the faces of some of the Reds as he collected the first yellow card of a north west derby, which is often known for being fiery.
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Gary Neville claimed after the game that the 19-year-old Tunisian is the only player who showed the heart and spirit required to be a Manchester United man at Anfield on Tuesday night.
The teenager has responded to the praise and claimed that he is always ready to fight and scrap when he dons the Manchester United shirt.
He took to Instagram and wrote: “Always an honour to wear this shirt.
“Always ready to fight for this badge.”
Mejbri is one of the bright young talents coming through the academy at Manchester United and the club paid €10m to sign him from Monaco in 2019.
He has already earned 12 international caps for Tunisia but the Liverpool game was only his second senior appearance for the Red Devils.
