The deal has been criticised by former Juve sports director Luciano Moggi, but he has hit the ground running at his new club.
Ferrari, of FK Sports Management, told tribalfootball.com: "Matri is a good player, with no international experience and comes from a small Italian club.
"But Juventus needed a striker that knows the Italian football style and to help the team score.
"Matri will score goals for Juve, even if the price of the transfer is high, as Moggi said."
Asked who were the kings of the winter market in Italy, Ferrari replied: "I think Inter had the best market campaign in January as they bought the players they needed and they took the best choices - not just replacement players."