The Argentina international has scored more than 100 goals in La Liga and Serie A during spells at Real Madrid, Napoli and Juventus.
Higuain has a wealth of experience after winning numerous top-flight titles in La Liga and Serie A.
The 30-year-old was linked with a reunion with Italian head coach Maurizio Sarri at Chelsea FC this summer.
Higuain netted 36 times in 35 games in Serie A during the 2015-16 campaign under Sarri’s management.
However, the South American opted to move to Milan ahead of a switch to the Premier League.
Speaking at his official unveiling at Milan on Friday, Higuain revealed why he opted to move to the San Siro ahead of Chelsea FC:
“In total sincerity, the esteem I have for Sarri is huge but he was the only who wanted me.
“Here at Milan everyone wanted me, and this is why I made my choice to come here.”
Chelsea FC finished in fifth place in the Premier League table last season to miss out on a Champions League spot.
The Blues were 1-0 winners against Manchester United in the FA Cup final to end the season with some silverware.
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