Palermo president Maurizio Zamparini believes Paulo Dybala could earn Juventus a staggering €150 million on the open market.
Dybala is a target for Manchester City, Real Madrid and Barcelona this summer.
Zamparini sold the Argentine to Juve 18 months ago.
After defeat to Juve last night, Zamparini said: "Beppe Marotta is a friend and I would like Paulo to remain at Juve. I think the club has the strength to hold such a player. Assaults there will definitely be, but I hope he remains for a long time in Turin.
"If he is a hundred million? Nah, worth 140 or 150. And he's the new Messi."