AC Milan controlled from the start and finally broke through in the second half to beat Napoli 3-0 Monday to open up a five-point lead over city rival Inter Milan in Serie A.
Zlatan Ibrahimovic, Kevin-Prince Boateng and Alexandre Pato each scored after the break at the San Siro.
Ibrahimovic converted a penalty in the 49th minute following a hand ball by defender Salvatore Aronica, Boateng finished off a setup from Pato in the 77th and the Brazilian then shot past two defenders from beyond the area in the 79th.
"It's a pleasure to play in this squad - a squad full of champions," said Pato, who has had an up-and-down season. "I always want to play and the coach chooses for the good of the squad. I'm just here to do my job."
Milan leads with 58 points, Inter has 53 and Napoli is third on 52.
"Napoli is still in the game, we've got to continue like this," said Milan manager Massimiliano Allegri.
Milan also dominated in the first half, but had trouble finding the target as Napoli gathered behind the ball en masse, while Napoli goalkeeper Morgan De Sanctis prevented an even more lopsided score with several difficult saves in the second half.
At the other end, Napoli forward Edinson Cavani, who has 20 goals this season, rarely saw the ball.
"We weren't able to play the way we wanted to," said Napoli coach Walter Mazzarri.
Netherlands midfielder Mark van Bommel was Milan's most dangerous player early on. He had an excellent look in the 34th but Aronica slid to block his shot.
Aronica also cleared a weak attempt from Pato off the line in the 40th and the Brazilian grew frustrated, drawing a yellow card when he slammed into Aronica near midfield a few minutes later.
Van Bommel had another chance two minutes into the second half which De Sanctis pushed wide.
After Ibrahimovic's goal, Pato nearly doubled the lead if not for a fingertip save from De Sanctis in the 55th. And De Sanctis made another difficult save in the 60th after Pato set up Robinho before Milan took control for good.
