The Danish side visit Old Trafford tomorrow night with the Red Devils needing to win, having suffered defeats to Bayern Munich and Galatasaray in the group stage so far.
Hannibal is wary of the danger the Copenhagen squad possess and issued Elias Achouri a plea.
Both are Tunisian and have struck up a friendship from their time together with the national team.
The 24-year-old is a talented winger, who has scored two goals and got six assists this season and he revealed what Hannibal said to him prior to the huge game.
Achouri opened up to Tipsbladet, saying: “He told me to chill a bit and not kill their players.
“I told him that I have to or at least give it a try.
“I said to Hannibal that we are going to win the match.
“I think we are going to exchange shirts after because he is my friend. It is going to be a cool moment for both of us.
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“I called Hannibal after the draw for the group stages and during the international break we talked about the match as well, so it will be exciting.
“I know him very well from the national team and both of us grew up in France, so we have a really good connection.”
Achouri is relishing the chance to play against Man Utd, adding: “It will be a huge moment for me, one of the greatest in my career.
“I need to stay focused and not let it get into my head.
“I’m professional and I’m going to Old Trafford to help the team and get a great result for the club.”
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