The club have since denied that Berlusconi had fired Allegri and his assistants, but the letter - read out on the Il Processo di Biscardi TV show - claimed the flamboyant politician and businessman would get rid of everyone, and had been making team selections himself.
“There will be a complete change in the coaching staff. We will also, if necessary, re-organise the club structure,” Berlusconi is alleged to have written after the club confirmed third place in Serie A.
But the club moved swiftly to deny any statements, saying: "President Silvio Berlusconi never give today any statement on AC Milan affairs, nor did he write the letter."
It is unclear whether Berlusconi was the author of the note, or if it was a prank by TV hosts after he failed to respond to requests for a telephone interview, which he regularly gives on the show.
According to the letter, Berlusconi implied he ordered Allegri to switch to a 4-3-3 system and credits himself with turning the season around.
“After the disastrous start to the season, I met with the Coach and directors to tell everyone this situation had to be overturned.
“I also specified that the team had to step on to the field with a different tactical set-up. The results were seen straight away, starting from the comeback to draw 2-2 with Napoli.
“From the relegation zone we climbed to third place, earned yesterday by the skin of our teeth.”
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