Juve meet Barca in the Champions League tomorrow night.
Allegri said, “Dybala will start tomorrow. He is 23 years old and he started out scoring many goals, then had a dip, because that's natural in the growth process. They are two very different players and move differently too.
“They have completely different physical as well as technical characteristics, as Messi is an explosive player and Dybala is more aerobic. Whether they can play together is not my problem!
“Messi is the only player in the world who knows how to turn and pass the ball where nobody else can. We must defend well as a unit. If the whole team doesn't help out, it's difficult to mark him.
“We are facing a side of great talent and quality, so need a super performance to bring home a positive result."