Del Piero is a former teammate of Conte's.
"First of all I would like to salute and thank Gigi Del Neri," wrote Del Piero on his official website.
"Regardless of how the season ended, the person and the Coach deserve recognition.
"As for Conte, I need say very little at the start of a journey that I hope will be as long and victorious as possible.
"Welcome back to Juve, Antonio. Welcome Mister Conte."