Milan claimed a famous 1-0 victory against champions Juventus on Sunday in front of a raucous Stadio Giuseppe Meazza.
The Rossoneri might just have ignited their rather mediocre season thanks to a controversial Robinho penalty.
The Bianconeri lost for the second time this season and gave a glimmer of hope to Inter and Napoli in the title race, both of whom can close to within one and two points, respectively.
Here are six things we learned from this massive game.
Mattia De Sciglio continues to grow as the season develops for the Rossoneri.
The Azzurrini international has been handed extra responsibility due to Luca Antonini and Ignazio Abate's struggles with fitness. De Sciglio is equally adept at playing on the left side of defence as his more favoured right flank.
Tasked with containing the explosive Kwadwo Asamoah—potentially Juve's player of the season—was never going to be an easy ask for the 20-year-old who has only played 12 league matches in his career for Milan.
De Sciglio applied himself excellently, superbly anticipating the Ghanaian's movement and tendencies to knock the ball past him and win a foot race.
Massimiliano Allegri will now know that De Sciglio has the ability to displace Antonini and Abate when they eventually return.
It has been presumed entering this new season that Mirko Vucinic was to be the first-choice striker and that the rest of the squad would battle it out for the opportunity to partner the Montenegrin.
Fabio Quagliarella has been in sensational form and Sebastian Giovinco would operate better in a role similar to that of Vucinic, who is given a license to roam freely into the wide and deeper areas.
Alessandro Matri and Nicklas Bendtner, while lacking the quality required by The Old Lady, are better suited in their styles to lead the attack than Vucinic.
The proposition of Juve signing a more clinical No. 9 would potentially push the 29-year-old out of the side if he does not begin to improve his performances quickly.
Antonio Nocerino found himself out in the cold at the beginning of the season, but his emergence into the side has coincided with an upturn in form for the Rossoneri.
Allegri has inserted the Azzurri international into the side, transforming the formation from an expansive 4-2-3-1 into a 4-3-3.
Nocerino is then given the freedom to bomb forward and chase the opposition with an intense pressing style that rushes the opposition in possession. The former Palermo midfielder can also move over to the flank in order to provide extra cover to the full-backs.
Brimming with passion and pride, Nocerino relished the opportunity to start the Juventus match and show the manager exactly what he can provide the side.
Nocerino has a lot to do with the intense tempo to the match that troubled Juve so much and it will not be surprising if he can cement his place back in the side over the coming weeks.
Milan's main problem this season remains finding a replacement for Zlatan Ibrahimovic, as Massimiliano Allegri has chopped and changed throughout the season in search of a focal point to their attack.
Kevin-Prince Boateng was tried there against Juve, while Bojan Krkic and Gianpaolo Pazzini have also been tested through the middle. Robinho and Stephan El Shaarawy appear to feel more at ease from wide areas.
Alexandre Pato's future appears in doubt after he voiced his frustration at being overlooked for Milan's Champions League match with Anderlecht. It now seems that the Brazilian will arrange a meeting to discuss his future moving forward.
Milan's priority then, moving forward, must surely be to target a traditional striker who can provide the goals as well as contributing to the system.
If Milan are to claim a Champions League spot, then it seems like Allegri will have to decipher how to solve his striking problem before long.
Antonio Conte has almost completely his ideal starting lineup and when everybody is fit, it makes Juve appear to be one of the most formidable sides in Europe on paper.
The Bianconeri cannot categorically say who is their starting right midfielder after several months of the season. Stephan Lichtsteiner appeared to be the preferred option, but the return of Mauricio Isla from injury has complicated matters, perhaps even unsettling the side.
The Chilean put in a dreadful performance against Milan, allowing Kevin Constant to comfortably cope with Juve's threat down the right.
Simone Padoin filled in after the break, but Juve must ultimately prepare an ideal side in order to combat the Champions League moving forward.
Milan appear to be over the turmoil that surrounded the club over the last couple of months, and a victory that signified redemption for last season's robbery against the Bianconeri will provide a huge boost leading up to the Christmas break.
The Rossoneri remain 10 points from second-place Fiorentina and Inter, who occupy the remaining two places that Serie A has on offer to qualify for the Champions League.
With the Viola's relative lack of experience as a team, Milan will fancy themselves to finish above them over the course of a season. Inter and Napoli face tricky away fixtures against Cagliari and Parma respectively and could not be definitively described as superior outfits to Milan.
With the side settling into a new, more balanced formation, Milan look a far better side, capable of shutting out the champions.
Having handed their rivals a significant head start, it is going to be tricky for Milan to reclaim a top-three position, but the squad is equally as talented as those who also share an ambition to play in next season's Champions League.