The Italian international defender headed home to cancel out David Suazo's opener just before the break.

The draw cut Juventus lead to just five points clear off second-place Milan, who beat city rivals Inter on Saturday, with four matches to go.

Honduran striker Suazo opened the score for the hosts in the 44th minute from the penalty-spot after Antonio Langella was clipped by Juve defender Gianluca Zambrotta inside the area.

Juventus had the chance to equalize in the 57th minute when they were awarded a penalty-kick but veteran striker Alessandro Del Piero failed to deliver as his shot was saved by his former teammate and Cagliari keeper Antonio Chimenti.

In the 95th minute, just when Cagliari fans started to get ready for the valuable victory celebrations, Cannavaro towered above all the defenders to head home Mauro Camoranesi's corner.

Elsewhere, a remarkable comeback by Palermo earned them a 3-3 home draw with AS Roma.

Palermo were three goals behind at halftime after Roma Brazilian midfielder Alessandro Mancini scored twice before Rodrigo Taddei added the third.

David Di Michele pulled one back for Palermo early in the second half before Simone Barone notched a brace to give his side a deserved draw.

Roma fell to fifth place with 64 points, one adrift of fourth-placed Fiorentina, who beat Treviso 3-1 thanks to goals by Luca Toni, Christian Brocchi and Riccardo Montolivo.

In other matches, Chievo beat Messina 2-0, Empoli edged Siena 2-1, Lazio defeated Livorno 3-1, Udinese cruised past Lecce 2-1, Reggina downed Ascoli 2-0 and Parma beat Sampdoria 2-1.