Balotelli formally signed for the Reds yesterday.
"We worked well together, Mario. We've been happy to have had you here and for this we say good-bye and thank-you," a statement on their official website read.
"In one year and a half you've achieved a lot. You were decisive in our qualification for the Champions League in 2013 and were our top-scorer last season.
"This is what your Milan thinks of you and this is our chance to confirm it publicly.
"There have been lots of memorable moments. The goal-scoring debut versus Udinese, that late winner versus Torino at the San Siro in May last year, the decisive goal against Siena and the screamer against Bologna on Valentine's Day at the San Siro.
"Thank you for everything and for what you have done at the club. We wish you the very best of luck for your next sporting and professional adventure."
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