Mario Mandzukic scored the only goal as Juventus killed off Inter Milan's challenge to move 11 points clear in Serie A on Friday.
Luciano Spalletti's third-placed Inter fall 14 points adrift of the leaders with the Derby d'Italia defeat a grave blow to their hopes of challenging for a first title since 2010.
Unbeaten Juventus have 43 points from 15 games -- 11 points ahead of second-placed Napoli who host lowly Frosinone on Sunday -- with their only points dropped coming in a home draw against Genoa.
World Cup runner-up Mandzukic's diving header after 66 minutes off a cross from former Inter player Joao Cancelo was enough to decide the outcome at the Allianz Stadium.
"Mandzukic is one of those players who even on an off day can bring his physicality to the game and that can make the difference," said Juventus coach Massimiliano Allegri.
"We knew the championship wouldn't end today, but we still absolutely had to avoid defeat.
"I asked the lads to be efficient and effective. We were only half that in the first period, but then we started to hold the ball with greater patience, were more organised and solid.
"After that, the quality of the players inevitably emerges."