Gustavo German Denis scored his first Serie A goal to continue Napoli's incredible run and doom Bologna to a fourth defeat on the trot.

The pressure is building on Daniele Arrigoni as the historic opening win over Milan was followed by four straight defeats and not a single goal in front of their home crowd. It was a tough ask against an unbeaten Napoli side that was just one point off leaders Inter going into this weekend. Miguel Britos was banned and Marcello Castellini injured, while the visitors were without Ezequiel Lavezzi, Gennaro Iezzo and Mariano Bogliacino.

Sergio Volpi's free kick skimmed the far top corner, while Marek Hamsik went on a trademark counter with his left-foot finish deflected out for a corner. Lanna couldn't get enough power on his volley from eight yards.

Bologna went close when Aronica handled on the very edge of the box and Martins Adailton's free kick skimmed the top corner of the net.

Marco Di Vaio nodded a Christian Amoroso cross on to the side-netting and after the restart Zenoni's angled drive was wide.

Moras did well to charge dow Marcelo Zalayeta's turn from nine yards on Michele Pazienza's assist, then Volpi's clearance fell to Pazienza for a fierce strike just over.

Bologna threatened as a Terzi header was deflected just wide from a corner kick, but Zalayeta's scuffed volley was easy prey for Francesco Antonioli.

Matteo Gianello smothered a Gaby Mudingayi strike, but it was Napoli who eventually broke the deadlock just three minutes from time. Summer signing - and substitute - Gustavo German Denis rose for a towering header from a Walter Gargano corner kick.