"One, two, three … the treble is coming for you," read the absurdly enormous Nightmare on Elm Street-themed banner stretched across almost the entire Curva Nord by Internazionale fans when they faced Milan in the Derby della Madonnina last November. The words rang hollow then, as Milan inflicted Inter's first home defeat since November 2008, but two months on they seem rather prescient. Much like Freddy Krueger, Inter's title challenge just won't die.

Milan's win that day took them six points clear of their rivals and through the remainder of 2010 the gap continued to widen. By the time Rafael Benítez had exited in a blaze of acrimonious glory after a Club World Cup triumph, Inter were seventh, 13 points behind the leaders. Although they had two games in hand, Milan's form rendered the gap a daunting one. One of the first questions put to the new manager, Leonardo, was whether he believed winning the Scudetto was still possible.

In the space of three games, the picture has changed. Three consecutive victories for Inter, capped by Saturday's 4-1 rout of Bologna, have seen the manager rechristened by Gazzetta dello Sport as "Leonardo dai-vinci" (Leonardo of the wins) and Inter's title odds fall from 7-1 to 7-4. Milan remain the favourites, but after dropping four points over the same spell there is a sense that their hold on this league is slipping. Inter are still nine points behind the leaders, but win the games in hand and the gap will be cut to just three.

If Inter are not yet haunting the Milan manager Massimiliano Allegri's sleep, he will certainly be finding them hard to avoid when he is awake. In the press conference before his team's 1-1 draw with Lecce, Allegri was forced to insist he was not "afraid" of Inter. In Gazzetta dello Sport's subsequent report of Milan's 1-1 draw at Lecce almost 100 words are expended on the Nerazzurri before either of the two teams involved in the match are even mentioned.

The reporter in question excuses his going off on such a tangent by asserting that Inter's improved form has had a negative impact on Milan's mindset, but he could be excused for being distracted himself. Under Leonardo, Inter have become a joy to watch once again. On Saturday at San Siro they tore apart a Bologna defence that had not conceded in their last four away games. If Dejan Stankovic's opener was marred by a hint of offside then Diego Milito's backheel flick to Samuel Eto'o for the third was unimpeachable.

Nor was this a one-off. A 4-1 win over Bologna means the team have scored nine in three Serie A games under Leonardo – or 12 in four if you include the Coppa Italia win over Genoa. To put that into perspective, Inter had only managed 20 in 15 league games under Benítez.

The Brazilian is no magician, nor even a particularly special tactician – Inter are yet to keep a clean sheet since he arrived – but a team who won almost everything there was to win in 2010 did not have need for either. After five consecutive Serie A titles, there has never been any doubt that these players could contend if their minds were in the right place and their bodies in the right condition.

The manager addressed the latter point by abandoning Benítez's gym-based training regime in favour of a return to the extensive ball-work used by José Mourinho, with a particular focus on working in confined spaces to increase players' explosiveness. It was telling that after scoring Inter's second goal, and only his fourth in the league this season, Diego Milito should run to celebrate with the team's fitness coach Stefano Rapetti.

The mental aspect the manager addressed simply by being himself. Where Benítez could be stand-offish with his players and was often accused of being too "scholarly" at Inter, Leonardo is warm and hands-on. Indeed, in his early training sessions it seemed that there was rarely a moment when he had his hands off his players, as he strode around the ground embracing the team before stropping to rest his arm on the nearest shoulder.

Perhaps more importantly, still, though, he helped those players to recapture the spirit they had found under Mourinho by openly invoking the Portuguese at every opportunity – as well as phoning the Special One frequently for advice. When Benítez took charge, Inter's directors felt compelled to take down a picture of Mourinho at Inter's Pinetina training ground, so he would not feel weighed down by the legacy of a man with whom he had plenty of previous. Leonardo, by contrast, has been happy for Mourinho to talk in recent days about helping to steer Inter even now from the "back seat".

Mourinho, for his part, has certainly not given up antagonising Milan, declaring this weekend that "this story will end the same as always: Scudetto for Inter". The Rossoneri may counter that Zlatan Ibrahimovic has won more domestic titles back-to-back than their rivals have but last night against Lecce even his absolutely extraordinary strike was not enough to secure all three points for a Milan team that suddenly seems unsure of itself.

With the first of their two games in hand coming up on Wednesday at home to 17th-placed Cesena, Inter have as good an opportunity as they could wish for to make Milan fans' sleep that little bit more fitful.

Talking points

• Is it possible that Ibrahimovic might be bad for fans' health? I mean, just look what his goal yesterday did to Adriano Galliani's face.

• Inter were not the only ones to take advantage of Milan's slip. Lazio, Roma and Juventus all gained ground with wins over Sampdoria, Cesena and Bari respectively, though none was especially convincing. Roma, most notably, scraped home only with a 90th-minute Maximiliano Pellegrino goal which really ought to have been disallowed for offside. Claudio Ranieri's troubles managing his squad were once again at the fore when Mirko Vucinic reacted furiously to being taken off with 10 minutes to go – understandably enough, as he had played well. But then, Ranieri's other option would have been to take off Francesco Totti, and we all know how that ends. Little wonder he said afterwards that he was "happy" to be linked with the Liverpool job.

• After the recent injuries to Fabio Quagliarella and Luca Toni it seems unlikely that the Juventus manager Luigi Del Neri would feel too much sympathy for the Tinkerman's abundance of options up front. Reports this morning suggest the Bianconeri will sign the Udinese striker Antonio Floro Flores on loan until the end of the season, but the move has not gone down well with the club's fans. Floro Flores has scored only 22 goals in 114 games at Udinese, and his Facebook page is awash with abusive messages from Bianconeri supporters telling him he's not fit to wear the shirt. Del Neri, at least, could empathise. "They said I wasn't worthy of Juve before I arrived here [too]," he said. "If Floro Flores does come, I hope he shows the opposite [to what everyone is saying]."

• Udinese, certainly, won't miss Floro Flores, without whom they scored four goals for the second time in as many games (albeit with a little help from the Genoa goalkeeper, Eduardo). Unlike with Milan last weekend, that was enough to get them all three points this time around. The hope among fans will be that Flores's departure (they are expected to receive €1.5m for the loan, plus a further fee if Juventus decide to make the move permanent in June), helps the club to hang on to the brilliant Alexis Sanchez a little while longer.

• Maurizio Zamparini v Serie A referees, vol. 6,000,247: "The only solution with these referees is to put them all in prison," railed the Palermo president, with justification, after Alessandro Matri scored Cagliari's opener against his team from an offside position. "The situation is becoming disgusting, just like the rest of what is happening in Italy at this time … This situation regards the whole country, and we are reaching the point at which the people won't have any choice but to come down to the piazza [to protest]. Now [refereeing designator Marcello] Nicchi owes us some explanations."

• And, just in case you missed it in David Hills's brilliant Said and Done column yesterday, here's a little more information than you could possibly have wanted from Lazio's Mauro Zárate:

Model Natalie Weber says her love for Lazio star Mauro Zárate "knows no bounds" ahead of their wedding in Rome this March. Natalie: "He is every woman's dream. The day will be so special for us." Mauro: "I use skin creams, perfumes and conditioners, and I will shave every hair off my body. I will look fantastic."

Results: Brescia 2-0 Parma, Cagliari 3-1 Palermo, Catania 1-1 Chievo, Cesena 0-1 Roma, Genoa 2-4 Udinese, Inter 4-1 Bologna, Juventus 2-1 Bari, Lazio 1-0 Sampdoria, Lecce 1-1 Milan, Napoli 0-0 Fiorentina

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