Inter Milan's struggles at the beginning of the season are a fast-fading memory as they go into Sunday's derby against AC Milan.
A few months ago Inter were on the verge of falling into the relegation zone, but the Nerazzurri have hit back with a vengeance and last weekend's 5-0 triumph over Parma was their seventh win in the last eight league games.
Claudio Ranieri's side have conceded just one goal in their last five league games and the victory over Parma moved them up to fifth place, eight points behind leaders AC Milan after 17 games.
"I hope I'm wrong, but I believe that Inter will be in contention for the title until the very end,'' AC Milan coach Massimiliano Allegri said. "They are in good form and I expect a very difficult game against them.''
Milan, who beat Atalanta 2-0 in Bergamo last time out to make it three wins in a row, are unbeaten at the Giuseppe Meazza stadium this season.
Unbeaten Juventus are level with Milan on 37 points and could take over sole possession of first place if they beat Cagliari in Sardinia on Sunday and Milan fail to take all three points.
Lazio, who are fourth, were awful in a 4-0 hammering at Siena last week and will be looking to show a huge improvement in Sunday's game against Atalanta.
Udinese will try to bounce back from their midweek Coppa Italia elimination at the hands of Chievo when they visit Genoa on Sunday.
Francesco Guidolin's side lost 2-1 to Chievo on Wednesday to see their unbeaten run at the Friuli Stadium this season come to an end.
Napoli coach Walter Mazzarri could hand new signing Eduardo Vargas his Serie A debut on Monday when his side host Bologna.
The Chilean forward joined Napoli earlier this month from Universidad de Chile.
Roma are looking to end a fantastic week on a high note when they face Catania and their former coach Vincenzo Montella in Sicily on Saturday.
The Giallorossi beat Chievo 2-0 last weekend for their third straight league win and set up a quarter-final tie with Juventus after a 3-0 triumph over Fiorentina on Wednesday in the Coppa Italia.
Palermo will seek their first win under coach Bortolo Mutti on Sunday at Chievo.
Mutti managed a 2-2 draw at Novara in his first game in charge in December, but suffered a 3-1 home defeat to Napoli last week.
Palermo sacked Devis Mangia before the Christmas break.
Fiorentina finally ended their dismal run on the road with a 3-0 triumph at Novara last time out.
The result was the Viola's first win away from home in the league since April 23 and they host bottom side Lecce on Sunday.
Parma begin life under new coach Roberto Donadoni when they host Siena on Sunday.
Last weekend's 5-0 defeat at Inter Milan brought to an end Franco Colomba's tenure at Parma, who have not won since a 2-0 triumph over Udinese on November 20.
Novara have won just two league games this season as they head into Sunday's clash at fellow relegation strugglers Cesena.