The Bianconeri head into the encounter in Turin's Stadio Olimpico unbeaten and on the back of a narrow win at Chievo on Wednesday.
An own goal from Alessandro Bernardini handed the Italian champions a 2-1 victory - their second consecutive in Serie A.
The result lifted Antonio Conte's side to third in the standings, two points behind leaders Roma.
"It's not going to be an easy game," Barzagli said. "Derbies never are and we need to be ready to suffer just as we did at Chievo in order to come out triumphant.
"We need to be focused from start to finish and not giving any spaces to (Alessio) Cerci, who is doing a great job."
Midfielder Arturo Vidal and strikers Mirko Vucinic and Carlos Tevez are set to return to the starting line-up against Torino after being benched at Chievo.
Cerci, meanwhile, would like nothing more than to score on Sunday.
The Italian forward leads Serie A's goalscoring charts alongside Fiorentina's Giuseppe Rossi with five goals this season.
"I have never scored in a derby, but I guess it must be a fantastic feeling," Cerci said. "I hope to achieve this and contribute to my team winning on Sunday.
"We have not won the derby in a long time and my team-mates and I will try to produce a perfect performance."
Torino have not beaten Juve since 1995 and head into the game on the back of Wednesday's 2-2 result against Hellas Verona.
Giampiero Ventura's men looked to be heading for their third triumph of the campaign only for Verona to equalise from the penalty spot midway through the second half to earn a point.
The outcome followed their 2-1 win over Bologna and lifted the Granata to eighth place.