Milan open the season this weekend against Torino.
Fonseca said: "It's too early to say whether it is the strongest group I've ever coached, but it's very strong. I don't change what I said at the first conference: we are here to win. With each passing day I have more confidence in this here to fight for the Scudetto.
"There has been a big change, our way of thinking and playing matches is different. I don't want to say that we will start from first place, but we are close to first place to start this match."
Asked if Inter Milan are the team to beat, Fonseca added: "It's clear to everyone: they clearly won the Scudetto last year. Then there are many teams that have the same objective as us. Even Napoli and Atalanta, Juventus can fight. We believe and want that we can stay in the fight with Inter.
"They are strong, they have confirmed the same players and the same coach, it is a very strong team."