David Trezeguet scored his league-leading 11th goal of the season on Sunday to help Juventus beat Palermo 5-0 in the Serie A, while AC Milan edged Cagliari 2-1.
Trezeguet scored with an overhead scissors kick in the 29th minute. Vincenzo Iaquinta, Alessandro Del Piero and Marco Marchionni also scored to give Juve its first win in three league games.
"I was worried because it was difficult to pick up after the [international] break," Juventus manager Claudio Ranieri said. "But when we understood how to play, it went very well."
Iaquinta had two free kicks saved before scoring in the 41st minute. Pavel Nedved also had a goal-bound shot blocked by Palermo captain Andrea Barzagli.
Del Piero made it 3-0 with a curling free kick in the 71st, three minutes after replacing Iaquinta, and completed the rout from the penalty spot in the 90th.
Marchionni got the other goal with a diagonal shot from inside the area in the 75th.
"We were too afraid," Palermo manager Stefano Colantuono said. "We took the wrong attitude onto the pitch. It seemed almost as if we knew that sooner or later they would score."
Andrea Pirlo secured Milan's fourth victory of the season with a long-range free kick in the 86th.
Alberto Gilardino poked in Milan's first goal in the 61st, after Roberto Acquafresca headed Cagliari into the lead in the fourth minute.
"It was an important victory for how it came about," Milan coach Carlo Ancelotti said.
Milan could have won by a larger margin but Cagliari goalkeeper Marco Fortin saved a 44th-minute penalty kick by Kaka after Ronaldo was fouled in the area.
"Kaka was a bit off form today compared to normal, but he kept Cagliari's defense worried constantly," Ancelotti said.
Also, Fabio Quagliarella scored in the 43rd and Antonio Di Natale in the 80th to lead 10-man Udinese to a 2-0 win over Siena, lifting the club into a tie for second place. Udinese defender Felipe was sent off in the 45th for his second yellow card.
Depleted by injuries or suspension to seven first-team regulars and without injured coach Cesare Prandelli, Fiorentina hung on for a 0-0 draw against Reggina.
Marco Zalayeta scored on either side of halftime to help Napoli beat Catania 2-0; Livorno won 3-1 at Sampdoria to climb off the bottom of the table; Fabio Firmani hit a deflected shot in the 90th to help Lazio beat Parma 1-0; and Empoli held Torino to a 0-0 draw.
On Saturday, Inter Milan beat Atalanta 2-1 to maintain its lead in the Italian league, and AS Roma edged Genoa 1-0 on a late goal by Christian Panucci.
Inter lead the Serie A with 28 points, followed by Juventus, Roma and Udinese with 25, and Fiorentina with 24. Inter, Roma and four other teams have yet to play their matches from the last round. Milan is ninth with 17 points.
Milan fans were unable to celebrate the result at Cagliari's Sant'Elia stadium. The soccer league banned Rossoneri supporters and those of another 12 teams in Italy's top three divisions from traveling to this weekend's games following riots sparked by the fatal shooting of Lazio fan Gabriele Sandri by police two weeks ago.
The other Serie A teams to play without their supporters were Atalanta, Catania, Roma, Sampdoria and Torino.
Ronaldo was unlucky not to score on his first appearance in the league in six months following a thigh injury, hitting the post in the 53rd.