Former Inter Milan front-man Zlatan Ibrahimovic fired a penalty kick past goalkeeper Luca Castellazzi five minutes into the match to give AC Milan a famous 1-0 win over their city rival, marking the first time Milan have won the Derby della Madonnina since Sept. 28, 2008.
Milan came out firing on all cylinders. Max Allegri's side dominated the beginning on the match, the highlight being when Ibrahimovic was taken out by Marco Materazzi inside the box to earn a penalty for the visitors. The Swede converted for his sixth goal of the Serie A campaign.
For some time after that, Milan continued to pile the pressure on the five-times consecutive champions of Serie A. During this time, Milan was unable to find the net again or even get a shot on goal, despite several excellent chances to strike.
Inter, plagued by injuries, were able to regain some momentum as the half drew on. The game truly started to turn in favor of Rafa Benitez's men when Joel Obi was forced off with injury and was replaced by Phillipe Coutinho. The young Brazilian brought some spark back into Inter's attack.
At halftime, both sides made substitutions, with Milan bringing in Andrea Pirlo for Gennaro Gattuso and Inter taking off European Club Player of the Year Diego Millito for Goran Pandev.
It was Pandev's entrance that led to drama only a derby between clubs that hate each other so much could provide.
Ignazio Abate received the first of Milan's five yellow cards in the 11th minute for a push on Samuel Eto'o when he got none of the ball.
He would receive Milan's third card as well, one that will raise some question marks about the performance of referee Paolo Tagliavento.
Abate had just returned to the field after being stretchered off for a knock he picked up. Allegri was about to put Luca Antonini in when Abate ran back on. Moments later, Abate got into it with Pandev.
The controversy escalated when Pandev blatantly shoved the defender to the ground with both hands intentionally.
Abate got up and only needed to raise his arms in a threatening motion and nothing more for Tagliavento to pull him aside and show him his second yellow, resulting in a red and forcing the Rossoneri to 10 men with a half hour to play. Pandev escaped with merely a yellow.
Antonini still came on in place of Robinho to prepare Milan to dig in and play 30 minutes of pure defense.
That would not be all though. Five minutes later, notorious bad boy Marco Materazzi jumped at Ibrahimovic with both feet pointed right at him.
Ibrahimovic put himself into a defensive posture to prevent a painful impact and ended up colliding with Materazzi, who did not get up. It was Ibrahimovic who surprisingly was given the booking.
Inter, led by Coutinho, Wesley Sneijder, Dejan Stankovic, and eventually the quick pace of Jonathan Biabiany, continued to march into the attacking third and fire shot after shot, whatever they could muster, at a strong Milan wall of nine defenders.
However, Milan were able to hold out until the final whistle and earn a crucial three points over their stadium-sharing rivals.
The win returns Milan to the top of Serie A, where they had been following the end of the last round of fixtures.
The Derby was the conclusion of a weekend of fixtures which saw all six of the top teams in Serie A face off.
With Milan and Lazio winning over Inter and Napoli and Juventus and Roma sharing the spoils, the race is starting to split ever so slightly into a battle for the Scudetto and a battle for the Champions League.
Milan hold a one-point lead over the Eagles, who are now four clear of Napoli, who remain third.
It is of course still early, but it has been proven time and again how difficult it can be to make up points on a club in top form.
Milan will be helped by the words of faith given by club owner Silvio Berlusconi, who told the club that a win over Inter would mean they win the Scudetto this season. The Rossoneri last held the trophy in 2004.
There are still 26 matches for each club in Serie A and a lot of questions still need to be answered.
Can Milan and Lazio continue to stay ahead of the pack? Can Inter get back to the form that earned them a Treble last season?
To this point compared to last year, Inter are nine points worse than they were a year ago. Milan are four points better. Lazio are by far the most improved. Through 12 rounds compared to last year, the Roman club are 14 points better off!
Roma, Juventus, and Napoli are the other clubs have a shot at the title, but can they continue to mount pressure on the leaders? All of these questions will reveal themselves throughout the rest of the campaign.
For now though, Milan will celebrate a hard-earned victory and begin preparations for Saturday's clash with Fiorentina at the San Siro.