Juve snapped up the veteran midfielder last summer when AC Milan chose not to offer him a new contract after 10 years at the San Siro, and Pirlo went on to help his new club win the Scudetto.
His performances during Euro 2012 have brought to wider attention just how much the 33-year-old still has in the tank.
"I think Pirlo has been the best signing of my career," Juventus general director Giuseppe Marotta said to Italian TV station RAI.
"There are certain situations that go in your favour, just as when I brought (Antonio) Cassano to Sampdoria (2009).
"Pirlo has been superlative."
Pirlo set up Antonio Di Natale for Italy's only goal in their tournament-opening draw with Spain and then scored with a free-kick in the Azzurri's 1-1 result with Croatia.
After a steady performance against the Republic of Ireland, Pirlo was successful with a cheeky chip in the penalty shootout against England in the quarter-finals.
Against Germany in the semi-finals, Pirlo enjoyed his finest display of Euro 2012, dominating in the centre of the park to help the Italians reach their third continental final.
"The important thing is that next season he continues to make the difference," Marotta said. "He is a great professional.
"You cannot put a price on players like him.
"Pirlo has an absolute value."
Pirlo is under contract with Juve for another two seasons.