The attacker has only featured once in the Premier League this season for the Red Devils.
Diallo, 21, starred in the Championship last season during a loan spell at Sunderland.
He scored 14 goals in 39 league appearances for the Black Cats as he helped them finish in a play-off spot.
However, this season, Diallo has found game time hard to come by.
The former Atalanta ace missed the start of the campaign with an injury, but since his recovery, he has not been able to cement himself in Erik ten Hag‘s team.
The manager has often opted to play Alejandro Garnacho, Antony or Marcus Rashford ahead of Diallo.
The Ivorian is now keen on a return to the Stadium of Light on loan for the remainder of the season, according to the Daily Mail.
Manchester United fans however are fuming that the winger has not been given a chance to shine.
One posted: “We don’t appreciate what we have till it’s gone.”
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A second commented: “Amad doesn’t deserve this treatment.”
A third wrote: “Please go Amad. Ten Hag will continue to disrespect you and pick his favourite Antony.”
A fourth said: “Good for him. Regular football is the most essential thing for him.”
A fifth added: “Kid is frustrated rightfully so, he wants to play and for whatever reason doesn’t seem like he’s going to be given a chance.”
Diallo would be the 13th player to leave Old Trafford this month should he get a move should Facundo Pellistri’s move to Granada be completed.
The likes of Donny van de Beek, Jadon Sancho, Hannibal Mejbri and Alvaro Fernandez have all left on loan.
Sergio Reguilon also left the club after his loan spell from Tottenham came to an end.
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