AC Milan completed four Serie A games without scoring for the first time since 1984 as they were held 0-0 at next-to-bottom Frosinone.
The result, and another lacklustre performance, against the team with Serie A's worst defensive record heaped more pressure on Milan's beleaguered coach Gennaro Gattuso.
Italian media reported that Gattuso could be fired during the winter break if his team do not improve.
Samu Castillejo hit the post for Milan while Frosinone, who have shipped 36 goals in 18 games, had a goal disallowed before halftime.
Camillo Ciano volleyed home from Raffaele Maiello's pass but, following a VAR review, the referee ruled that Maiello had fouled Hakan Calhangolu as he won the ball in midfield.
In an end-to-end finale, Milan striker Gonzalo Higuain fired over the bar from 12 metres in stoppage time from Calhanoglu's inviting pass as he completed his ninth game without scoring.
Goalkeeper Gianluigi Donnarumma came to Milan's rescue with an excellent save from Ciano's low drive.
Milan stayed fifth with 28 points but are in danger of being engulfed by a pack of teams just below them.