"I can confirm that Marco Storari will start (in place of Buffon). It's a normal rotation that we also did last year," Conte told a news conference.
"Buffon is coming from international duty and we have another four games in quick succession ahead of us, so together with him and the fitness coaches we decided to rest him."
Llorente was sidelined by Bilbao manager Marcello Bielsa after refusing to sign a deal with the Basque club and was mostly used as a substitute.
He agreed to join Juve in January but has hardly played this season, leading to speculation that he will leave.
"He's not played for a year and he's needed more time to rediscover his best form, the necessary intensity and on field aggression, both his and that of the opposition. When you don't play for a year you lose these things," said Conte.
"It could be that he plays tomorrow, or that he plays Wednesday, or next Sunday."