The midfielder says the Brazilian has arrived full of energy.
“Kaka is more mature now and I am sure he’ll give us a big hand,” Muntari told Milan Channel.
“He is one of the best trequartisti in the world and is able to create space for us to push up from midfield.
“We are a great group of players with many youngsters, but also a good selection of the old guard like Daniele Bonera, Christian Abbiati and Nigel De Jong to help strengthen the squad."
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