Security controls will be extra tight at Serie A matches this weekend after Italy's Euro 2012 qualifier against Serbia was abandoned due to violent Serbian fans.
European champion Inter Milan visits Cagliari without striker Diego Milito and midfielder Esteban Cambiasso, who both picked up leg injuries during Argentina's loss to Japan last week.
Surprise leader Lazio plays at Bari, AC Milan hosts Chievo Verona, and Juventus meets newly promoted Lecce.
Struggling AS Roma, which has won just one of its opening six matches, plays Genoa.
While security chief Roberto Massucci says Italian fans were not responsible, there are worries that some hard-core supporters could show solidarity with the Serbian rioters.
Questions remain about how Italian police allowed the Serbian fans to enter the Luigi Ferraris stadium in Genoa on Tuesday armed with an arsenal of fireworks, flares and other destructive material.
"We're going to check the fans even more closely Sunday," Massucci said.
Inter captain Javier Zanetti is also still doubtful with a chest problem that has already kept him out for three matches - an eternity for a player who hadn't missed a Serie A or Champions League game through injury in five years.
"I have one last test Saturday and then I hope I'm all clear for Sunday," Zanetti said, also lamenting the injuries to Milito and Cambiasso. "These are things that happen over the course of a season, although unfortunately they've all come at the same time."
Inter, Napoli and Milan are tied for second with 11 points each, two behind Lazio.
With newly signed Brazilian playmaker Hernanes and a rejuvenated Stefano Mauri leading the way, Lazio has won four its first six games and can also rejoice over bitter rival Roma's position in the penultimate spot in the table.
"We're fortunate in that we have players with a lot of quality, like Hernanes, (Mauro) Zarate and (Sergio) Floccari, who can decide a game at any time," said manager Edy Reja.
England coach Fabio Capello comes from the same region in northern Italy as Reja and the pair are longtime friends.
"(Lazio) can finish in the top four and get into the Champions League," Capello told the Gazzetta dello Sport. "Edy is experienced, he knows football and knows how to control his squad."
Mauri was called back to Italy's national team for the first time in three years and started both a 0-0 draw in Northern Ireland and the match against Serbia, which was abandoned after seven minutes.
"We're not thinking about either the title or the Champions League," Mauri said. "We're only through six rounds so far and the only thing that counts is the final standings."
Milan goalkeeper Christian Abbiati is out for up to three weeks with a groin injury sustained in a win over Parma two weeks ago, opening up a starting position for Marco Amelia.
Milan is hoping to come out of the match against Chievo ready for its visit to Real Madrid and former Inter manager Jose Mourinho three days later.
Roma, which has only managed to beat Inter thus far, has several players doubtful due to injuries: forwards Mirko Vucinic and Jeremy Menez and midfielders Daniele De Rossi and David Pizarro.
Also this weekend, it's: Brescia vs. Udinese; Catania vs. Napoli; Cesena vs. Parma; Palermo vs. Bologna; Sampdoria vs. Fiorentina.
