The midfielder has been at the heart of Milan's domestic resurgence over recent weeks, and performed superbly during the midweek win over Barcelona in the Champions League against some of the most highly rated players in world football.
Maldini has been surprised at how well the Italy international has performed and compared the midfielder to Juventus' Pirlo, who left the Rossoneri for the Bianconeri on a Bosman transfer in 2011.
"Montolivo has really surprised me," Maldini told La Gazzetta dello Sport. "He's been consistent, he has quality and he's proved that he can adapt to a number of different roles.
"He's a decisive player, one who can fill the hole that was left when Andrea Pirlo moved on. He has physical strength, he wins back the ball, he has vision - he's got it all."
Milan faces a crucial derby with Inter this weekend, as the race for the top three in Serie A heats up.