Juventus climbed above Napoli with a 1-0 victory at Torino that maintains their pursuit of the Serie A title.
Alex Sandro's first-half finish proved enough to secure all three points, local bragging rights in the Turin derby, and to take Juve two points ahead of Napoli, but the hosts regardless remain in the relative safety of ninth place.
A wider concern for Juve manager Massimiliano Allegri as they balance chasing a seventh successive league title with the Champions League will be the loss, to a suspected ankle injury in the first half, of his striker Gonzalo Higuain after he collided with the hosts' goalkeeper Salvatore Sirigu.
The Argentina international was soon substituted, and his potential absence comes at a time when Mario Mandzukic, Juan Cuadrado and Blaise Matuidi are also all out injured.
Allegri had rested the 40-year-old Gianluigi Buffon and instead started Wojciech Szczesny, meaning that with the Italian goalkeeper's contract due to expire during the summer he may have played in his final Turin derby.
His team's goal came in the 33rd minute, from close range. After receiving possession on the right from Sandro, Higuain's replacement Federico Bernardeschi sent an untidy ball across the penalty area back towards the Brazilian, who routinely tapped into a near-open goal.
Substitute Paulo Dybala came closest to doubling their lead in the second half when first he struck wide from Bernardeschi's long ball, then when shooting over the crossbar after collecting Sandro's cross, and finally when forcing Sirigu into a save with his shot from outside the area.
M'Baye Niang also threatened for Torino but missed the target from a tight angle, and Iago Falque later tested Szczesny, but Juve resisted any pressure to usurp Napoli, who have played one fewer fixture and later on Sunday host struggling SPAL.