Zapata signed formally for Milan yesterday.
Maldini told TMW: "I remember him from Udine, he did very well, then at Villarreal has not done very well and has had an injury .
"But it is obvious that Milan will have followed the player and considered him fully recovered.
"I think he still is not exactly a central defender but inevitably some kind of welcome by the fans after the departure of Thiago Silva. The Brazilian is a phenomenal player that I believe could have had a long career with the Rossoneri like (Franco) Baresi or Paolo (Maldini).
"So I think we need a high level player in defence."