While the top-of-the table clash at the San Siro takes centre stage in Italy this weekend, Ronaldo will steal much of the limelight if he is deemed fit to make his debut for AC Milan at bottom club Ascoli.

Inter are 11 points clear of second-placed Roma after a record sequence of 14 consecutive Serie A wins a run that has prompted Italy's largest bookmaker to pay out on the 'Nerazzurri' retaining the championship.

The fat lady may be preparing to deliver her opening note, but Roma feel they could be the ones singing after Sunday's crunch match.

"We have the utmost respect for Inter, but if the real Roma shows up we can do it," said Chilean playmaker David Pizarro who joined Roma last year but is still half-owned by Inter.

"A win there will reopen the championship and we still believe the title race is far from over."

However, Pizarro's midfield partner Daniele De Rossi has his doubts whether Inter can be caught.

"Inter seem determined not to ease up, but unless they have a bad run there will be little we can do," said the tough-tackling Italy international.

Inter coach Roberto Mancini dismissed talk that the Scudetto was already in the bag.

"For us the championship is not over," he said. "We have a good lead, but on Sunday we face Roma -- a very dangerous team in form."

Roma will also meet Inter in the Italian Cup final after both sides came through their semifinal ties in the week.

Roma beat AC Milan 3-1 on Wednesday for a 5-3 aggregate victory, while Inter drew 0-0 with Sampdoria for a 3-0 aggregate win.

Roma's French centre-back Philippe Mexes is doubtful for Sunday's match after injuring his right foot against AC Milan.

Ronaldo is not certain to make his debut for AC Milan due to a lack of match fitness.

The 30-year-old Brazilian striker signed from Spanish giants Real Madrid on Tuesday but may sit out Sunday's match.

He had a stop-start season with Real due to injuries to his ankle and calf and is a little off the pace.

"He's getting better every day and only has a few problems to resolve," said Milan's chief medic Pierre Meersseman on Thursday.

"Initially I thought it would take a month before we would see him in action, but today there is hope he will be ready straight away.

"Ronaldo needs to train a bit more, but it's certainly a good sign that he is able to run without feeling any kind of pain."
Fixtures
(1400GMT kick-off unless stated)
Saturday
Reggina v Messina (1700), Livorno v Cagliari (1930)
Sunday
Ascoli v AC Milan, Empoli v Atalanta, Inter Milan v Roma (1930GMT), Lazio v Chievo, Parma v Fiorentina, Siena v Torino, Udinese v Sampdoria