Up to the 14th day of the season, Inter had already collected 35 points and had a 14-point lead over Roma. But, since the start of the second round, Jose Mourinho's Inter shifted their focus to Europe and their performances in the league suffered as a result.
Indeed, their tally of 22 points from 14 matches is testament to their downturn on the domestic scene.
In Europe, Inter ousted Chelsea and CSKA Moscow to reach the semi-finals of the Champions League but they have been rather erratic in their last 11 Serie A outings, only managing 15 points after three wins, six draws and two defeats.
Away from their Giuseppe Meazza stadium, Inter only recorded one win (over Udinese) and five draws in their last eight trips.
The once undisputed leaders of the Serie A have suddenly found themselves trailing Roma by a point.
Inter's failure to beat Fiorentina away on Saturday combined with Roma's 2-1 victory over Atalanta, their 23rd match without a defeat, meant that the Nerazzurri were knocked off the top for the first time since October.
Third-placed Milan, currently four points off the pace, are still in contention for the scudetto albeit the Rossoneri's bleak run of late - one win in their last five outings - suggests otherwise.
With five straight wins in their last five outings, Roma are brimming with confidence. On Sunday, they take on city rivals Lazio. Edy Reja's Sky Blues are on a positive run themselves.
Following last weekend's results, Lazio, last year's Coppa Italia winners, are six points clear of third-from-bottom Atalanta. Considering that Lazio will cross swords with bottom side Livorno and Udinese in their final two fixtures, one expects them to make sure of survival in those two games.
Apart from Roma, Lazio will also entertain Inter on the 36th day. They could, therefore, influence the outcome of this season's title race.
The rivalry between the two Rome clubs is so bitter, that even if Lazio were home and dry by now, they would still have a go at Roma with a view to upsetting their title hopes.
In the 1998/99 title run-in, Lazio, then managed by Sven-Goran Eriksson, eventually bowed out to Milan after losing two crucial fixtures - vs Juventus and Roma. The same could happen to Roma this season if they do not beat Lazio on Sunday.
In their other four fixtures, Claudio Ranieri's Roma will host Sampdoria and Cagliari and visit Parma and Chievo. Inter have two back-to-back home fixtures - against Juventus and Atalanta - before travelling to Lazio, hosting Chievo and finishing with a visit to Siena.
Both teams have tricky fixtures coming up. However, many believe that if Roma overcome Lazio next weekend, they will go on and claim their fourth scudetto - the first in nine years.
As things stand, the pressure is now all on Roma... they are the new pacesetters. Roma have their destiny in their own hands. Ranieri has to be tactful enough to keep his players on their toes. Roma have already done a massive job recovering lost ground this season.
Their early exit from the Europa League could turn out to be a blessing in disguise because, unlike Inter, they have since been able to focus on league commitments only.
By contrast, the Champions League has drained Inter's resources. It is not easy for any side to still be in contention for three major trophies at this stage of the season. In Europe, apart from Inter, only Bayern Munich are still in with a chance of a treble.
But, Roma now have the momentum to keep their winning streak going. Their new status as leaders brings added responsibility and therefore pressure to succeed.
How will they cope with it?
Serie A statistics
1 ST away win for Udinese who scored two first-half goals to become the eighth side to beat Livorno at the Armando Picchi stadium this season. Victory saw Udinese go seven points clear of third-from-bottom Atalanta. With only five games to go, bottom side Livorno, without a win in their last 14 outings, are nine points away from safety.
2 ND successive home win for Juventus as a Giorgio Chiellini goal was enough for them to see off Cagliari. The latter have been in a complete freefall lately, only managing two points from their last nine outings.
3 WINS and two draws from their last five games saw Lazio go six points clear of the drop zone. In a basement clash on Sunday against Bologna, Edy Reja's men came from two goals down to hand the home team their fifth straight defeat. Overall, Franco Colomba's Bologna are winless in their last six outings.
4 POINTS now separate Roma from third-placed Milan. The Rossoneri's third home draw on the trot (vs Napoli 1-1, Lazio 1-1 and Catania 2-2) has seriously dented their title aspirations. Last weekend, Milan came from two goals down to salvage a draw against in-form Catania. Leonardo's side have only managed one win (vs Cagliari 3-2) in their last five games. Genoa, meanwhile, have now gone five consecutive games without a win (three draws and two defeats) as they were floored by city neighbours Sampdoria.
5 TH straight win for new leaders Roma who edged Atalanta 2-1 in the capital. Two goals inside the opening half-hour gave Roma a headstart but the visitors pulled one back early in the second half to set up a tense finale. The Giallorossi's 23rd successive positive result coincided with Atalanta's fourth consecutive away defeat. Inter could not go beyond a 2-2 away draw with Fiorentina. Inter only managed three wins and six draws from their last 11 matches.
7 TH penalty in favour of Palermo during Sunday's match against Chievo. For the record, the Sicilians missed only once from the spot when Morgan De Sanctis stopped Miccoli's penalty in Napoli-Palermo (0-0) on the 20th day. Napoli striker Fabio Quagliarella and coach Walter Mazzarri were both expelled in the 3-2 upset at home to Parma.
34 GOALS were scored on the 33rd day: 18 coming from the hosts and the remaining 16 from the visitors. Foreign players contributed with 16 goals. Total number of goals scored so far is 848. Three players - Marco Borriello (Milan), Fabrizio Miccoli (Palermo) and Abdel Ghezzal (Siena) - scored a brace each. Lazio's Tommaso Rocchi was the only player who came on as a substitute and scored. Udinese forward Antonio di Natale is still the leading scorer with 23 goals.