AC Milan's worst start to a season since 1981 continued as they were held to a 0-0 draw at Chievo which further increases the pressure on coach Massimiliano Allegri.
It could have been even worse for the Rossoneri as Chievo saw a goal disallowed for offside midway through the second half, although Robinho hit the post on a frustrating afternoon for Milan at the Stadio Marc'Antonio Bentegodi.
Both sides ended the game with 10 men, Riccardo Montolivo followed down the tunnel by Sergio Pellissier towards the end of the match.
Chievo lined up, as expected, with eight men behind the ball, inviting the Rossoneri to attack them.
They were not completely negative, though, as they broke whenever they got the occasion, going close to opening the scoring in the 17th minute when Marcelo Estigarribia's shot from 30 yards seemed destined for the top left-hand corner before being pushed wide by Christian Abbiati.
When Milan did get through the massed ranks of Chievo players, Andrea Poli twice sent the ball wide of the post, first dragging a shot across the face of goal and then failing to make the best of contacts with a header from six yards out.
Milan were increasing the pressure and the half-time whistle was the only way to bring an end to their persistent attacks.
The second half started with another good chance for the home side, Cyril Thereau's shot parried by Abbiati to Rigoni, who - from a tight but not impossible angle - fired into the side-netting.
Chievo thought they had taken the lead in the 74th minute when Alberto Paloschi tucked the ball past Abbiati and in, but the linesman's flag was raised for a tight offside decision.
Milan continued to attack and Robinho should have given them the lead when he had only the goalkeeper to beat, but he casually placed his shot against the post with Kaka lifting the rebound over the crossbar.
The visitors were reduced to 10 men for the last seven minutes when Montolivo picked up a second yellow card but Allegri's men did not stop attacking, throwing caution to the wind.
Alessandro Matri and Robinho missed good chances before Chievo were also reduced to 10 men with Pellissier picking up two yellow cards in the space of a minute to join Montolivo in the dressing room, although his side held on.