Milan coach Massimiliano Allegri is finding out the hard way that four into three doesn’t go.

Since signing Italy striker Antonio Cassano in the transfer window, Allegri has had to juggle his attacking options by deploying two from Cassano, Alexandre Pato and Robinho alongside Zlatan Ibrahimovic.

Pato is the player most at risk of losing his starting place for Milan’s trip to Genoa tomorrow, after a run of injuries and poor performances.

In Tuesday’s 0-0 draw against Lazio the Brazilian made way for Cassano just after the hour and earlier in the season he complained about his relationship with Ibrahimovic.

“There is no problem with Pato,” Allegri said. “I took him off because the defense was closing him down quickly and Cassano works better in tight spaces.”

Milan are unbeaten in their six league games since the start of 2011 with three wins and three draws and are five points clear at the top of Serie A in pursuit of their 18th Italian championship.

The addition of Cassano, Mark Van Bommel, Urby Emanuelson and Nicola Legrottaglie during the transfer window has added greater depth to the squad, while a number of players are likely to return from injury and suspension in the next few weeks.

“The next match will be tricky, however we will have two or three players back and this is very important for us,” Allegri said. “I hope that Boateng, Gattuso, Seedorf, Van Bommel and Pirlo will be back.”

Second-place Napoli missed a chance to close the gap on Milan in midweek by slumping to a 2-0 defeat to Chievo.

New signing Giuseppe Mascara is likely to be included in the squad for the home fixture with Cesena and is confident that he can help Walter Mazzarri’s side recover immediately.

“I saw the match but I’m sure it is just a hiccup,” Mascara said. “It is difficult playing every three days but we have to be confident in ourselves.

“We are fighting for something very important, but I have found a very unified group of players.”

Defending champions Inter host last year’s runners-up Roma, who are without suspended France centre back Philippe Mexes.

Inter coach Leonardo meanwhile has a similar problem to his AC Milan counterpart. Giampaolo Pazzini scored twice on his Inter debut last weekend and Samuel Eto’o took his league tally to 13 in the 3-2 victory over Palermo.

The Brazilian can also turn to last year’s leading scorer Diego Milito and Goran Pandev up front as he tries to close the gap on Inter’s city rival.

“Of course we look at the table, but we aren’t obsessed with it,” Leonardo said. “We have still got a lot of matches until it is over and we know how hard it is to win just one game.

“We are just thinking about getting into a place where we can challenge and then we will see.”

Fiorentina are boosted by Adrian Mutu’s return to the squad for its fixture at Parma. The Romania striker was suspended after walking out on the team in early January.

Sinisa Mihaajlovic’s team beat Genoa on Wednesday to relieve the pressure on their beleaguered coach, after fans had protested outside the stadium following defeat to Lazio at the weekend, but Fiorentina is still without a win on the road since early February 2010.

“These three points are massive and it is an important win,” Mihajlovic said after the victory. “The guys gave everything - heart and determination - and this is how they should play.”

Today, it’s: Udinese vs. Sampdoria; Cagliari vs. Juventus. Also tomorrow, it’s: Bologna vs. Catania; Brescia vs. Bari; Lazio vs. Chievo Verona; and Lecce vs. Palermo.