​AC Milan CEO Marco Fassone has revealed that the club reached an agreement with Juventus to sign Leonardo Bonucci in "30 minutes".

The Rossoneri signed the defender in a surprise €40m deal, one of a number of high-profile, big money arrivals in the summer.

Fassone has admitted that bringing in the experienced Italy international had not originally been in the club's plans.

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“At the beginning he [Bonucci] was not in our plans," Fassone told ​Il Corriere dello Sport. "When Montella and Mirabelli told me we could have signed him I did not want to believe it. We went straight to the target and we’ve reached an agreement with Juventus in 30 minutes. Leonardo is a leader but is also a player capable to settle in well quickly.”

Milan's new additions, including Bonucci, looked to have settled in well following six successive victories to begin the season, but last weekend's 4-1 loss to Lazio was something of a reality check.

“This mustn’t change our ambitions, but it should serve as a valuable lesson,” Bonucci told Mediaset Premium after the defeat, via ​Football Italia.

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“I think we ought to treat this defeat as a healthy slap in the face for everyone. We didn’t have the belief that we’d hurt Lazio and so when they scored on their first opportunity, it knocked the wind out of our sails.

“The way I see it, defending begins when the opposition first get the ball, and it must be done together with aggression – that is what we’re currently missing.

“It was utopian to think that we’d be a super squad working like clockwork from the first day. We have to improve in many areas, enjoy keeping clean sheets and sacrifice ourselves for the team. That isn’t happening.”