
Inter, now on 24 points, were at ease despite the many absences as they took an early lead through defender Ramiro Cordoba, nodding home after a Hernan Crespo header against the bar.
Esteban Cambiasso tapped in Inter's second on 50 minutes as goalkeeper Rubens Rubinho failed to grab a free kick and Genoa pulled one back with Frenchman Abdoulay Konko on 73 minutes.
Just two minutes later, though, defender Gaetano De Rosa offered David Suazo an easy chance to score his first goal for Inter, while Julio Cruz rounded off for the blue-blacks from the spot.
In Rome, a hard-fought city derby saw Roma edge Lazio 3-2 to move on to 21 points from 10 games. Lazio took the lead with Tommaso Rocchi on 11 minutes, but were stunned twice before the break by Mirko Vucinic and Brazilian Mancini.
Simone Perrotta notched Roma's third goal before Cristian Ledesma on 70 minutes slammed home a free kick that settled the score on 3-2.
Montenegro striker Mirko Vucinic, who replaced the injured Roma captain Francesco Totti, confirmed a great form being on target for his third consecutive game.
"If my team mates hadn't lent me a hand, it would have been hard to come back (against Lazio)," he said.
Juve's David Trezeguet scored a hat-trick in a 3-0 win over Empoli to become the league's top scorer on 10 goals four days before a high-voltage match with visiting Inter.
Joint-third with Juve on 20 points are Fiorentina, who edged Napoli 1-0 through a goal from veteran Christian Vieri off an Adrian Mutu assist.
Udinese trail on 18 points after a 2-1 win over Torino in a game that both sides ended with 10 men, while AC Milan gave a sign of recovery from a glum period crushing Sampdoria 5-0 for a 13-point tally.
Alberto Gilardino scored his second brace this season after Brazil star Kaka opened the scoring, with the young Yohann Gourkuff and Clarence Seedorf also on target for the European champions.
Sicily side Palermo were held to a 1-1 home draw with Parma, Siena and Catania also drew 1-1, Atalanta and Cagliari played out a 2-2 draw, and Livorno are now joint last with Reggina after beating them 3-1.
DPA