ROME (AFP) - Ronaldo was the inspiration as AC Milan ended their dismal winless home run with a 5-2 victory over Napoli on a dream night at the San Siro on Sunday.

Ronaldo was playing only his second match of an injury-plagued season but scored a brace as he partnered debutant teenage sensation Pato in a new-look three-pronged Brazilian attack that included world player of the year Kaka.

Milan coach Carlo Ancelotti finally got the firepower that has been missing from the team at home in the league this season, as Pato and Kaka also got their names on the scoresheet.

In their previous seven matches - five draws and two defeats - Milan managed just three goals, they had doubled that tally 30 seconds into the second half against Napoli.

Ronaldo gave the hosts the lead on the quarter hour, latching onto Andrea Pirlo's clever through ball to fire home off goalkeeper Gennaro Iezzo's legs.

Milan were dominating but Napoli were dangerous on the counter-attack and soon levelled through Roberto Sosa, who converted fellow Argentine Ezequiel Lavezzi's right wing cross.

Ronaldo then tried to turn provider, twice teeing up Pato with just Iezzo to beat but the keeper denied him both times before Clarence Seedorf smashed home the follow-up.

Maurizio Domizzi then levelled from the spot after Georgia centre-back Kakha Kaladze's clumsy challenge on Lavezzi in the box, sending the teams in at half-time all square.

But just after the restart Seedorf picked out Ronaldo to head home from close in.

Kaka scored midway through the second half with a crisp shot from the edge of the box and minutes later Pato opened his account after racing clear and finally beating Iezzo in a one-on-one.

Elsewhere, Francesco Totti and Alessandro Mancini fired a goal apiece to give Roma a come-from-behind 2-1 victory at Atalanta to keep their title hopes alive.

Champions and leaders Inter Milan cruised to a 3-2 win at lowly Siena and when Roma fell a goal behind, it looked as if the title race could be over.

Instead the capital-based club pegged Inter's lead at the top to seven points, with third-placed Juventus dropping to 10 points back after a 1-1 draw at Catania on Saturday.

In the race for Champions League places, fourth-placed Udinese kept their noses a point in front of Fiorentina after a solid 1-0 win at Cagliari while the Viola triumphed 2-1 in Parma.

In Atalanta things looked desperate for Roma when Adriano Pinto put the hosts ahead on 17 minutes.

But Totti rifled home a free-kick under a jumping wall on 38 minutes and Mancini's rasping drive on the stroke of half-time proved enough to secure three vital points.

Totti admitted afterwards that Roma were not optimistic of catching the leaders.

"It will be difficult to catch Inter if they keep winning," he said. "They are just that little bit better than everyone else," said Totti.

"The important thing is to keep Juventus behind us, hold on to second place and hope that eventually the leaders slip up."

In Siena, Inter predictably coasted to a victory that was more convincing than the scoreline suggested.

Sweden forward Zlatan Ibrahimovic scored a brace, including one from the spot, and Esteban Cambiasso added the other as unbeaten Inter won for the 14th time in 18 league matches this season.

Inter coach Roberto Mancini continued to play down his team's insatiable march to the title.

"We're not even at the halfway stage of the season yet," he insisted. "The most important thing was to come back after the winter break and win."