The 19-year-old midfielder is regarded as one of the hottest prospects at Old Trafford and someone who is tipped to play a much more central role in the first team moving forward.
A Tunisian international, Mejbri has already made his senior debut for the Red Devils, with Ralf Rangnick also naming him as a substitute for the FA Cup fourth round clash with Middlesbrough last week.
Fans had better get acquainted with the talented starlet and talkSPORT.com takes a look at the player and what has been said about his undoubted potential.
Hannibal Mejbri: Profile
Born on January 21, 2003 in a suburb of Paris, Mejbri started his football career with Paris FC in 2009.
The attacking midfielder spent time with France's famous Clairefontaine academy, before joining AS Monaco.
Mejbri was then scouted by Manchester United, Manchester City, Liverpool and Arsenal, with the Gunners also taking the player on trial.
With interest from Paris Saint-Germain, Bayern Munich and Barcelona, the player moved to Old Trafford in 2019 for a reported fee of €5million, possibly rising to €10 million in add-ons.
Hannibal Mejbri: Coming of age
After moving to United, Mejbri wasted little time in making an impression as he established himself as a regular player in the under-23s side, despite being just 17 years of age.
An unnamed source told The Athletic: "He actually takes the p*** sometimes against players a couple of years older than him. He'll feint to strike then drag it and shoot the other way."
As well as making four appearances in last season's EFL Trophy, the midfielder was handed his senior debut in the final match of the 2020/21 season as he played eight minutes against Wolves at Molineux.
Discussing the player, Ole Gunnar Solskjaer said: "You drip-feed them in and you don't expect them to set the world alight. But you want to see them in this environment and he's looked comfortable and confident.
"Hopefully, we can give him that extra motivation and inspiration to show even more of his talent and why not?"
It was May 2021 when he declared his international allegiance to Tunisia by making his senior debut against DR Congo the following month.
Hannibal Mejbri: AFCON and first team breakthrough
While first team opportunities have been hard to come by this term, it seems that the 19-year-old is finally set for another opportunity, with Rangnick describing him as 'a good, highly-talented player'.
Mejbri has spent the last month at the Africa Cup Of Nations where Tunisia made it to the quarter-final stage.
The midfielder conducted an interview with Le Parisien while away and declared his intention to challenge for a spot in the first team, saying: "When I go back to United, we will see if there will be any changes for me and if I can try to earn a place in the team.
"In any case, I'll work hard for it."
That opportunity presented itself in the build up to the FA Cup fourth round clash with Middlesbrough in which Rangnick confirmed that the player would become a fully fledged member of his first team squad.
He said: "We have Hannibal included in the squad.
"He will, from now on, regularly train with us and be a regular member of the squad. He will also be part of the squad for tomorrow's cup game.
"I saw him play in the final [of the Arab Cup} and, from what I've seen so far, I think he's a promising talent. He deserves to be part of the group for the rest of the season and also part of the group for tomorrow's game."
Hannibal Mejbri: What next?
With much of the season left and United still competing in both the Premier League and Champions League, there could be opportunities for Mejbri to make an impact.
While a place in the starting line-up will be difficult to nail down due to the calibre of competition in his position, the hope for the 19-year-old is that he can be in and around the matchday squad on a regular basis and add to his senior appearances in the process.
He has been included in their ranks for the Premier League trip to Burnley on Tuesday, February 8.