JOSE MOURINHO needs no second invitation to revel in victory, but this 2-0 triumph over his fiercest rivals at a seething San Siro will have felt more special than most.
Internazionale's well-earned triumph over a Milan side, who failed to find inspiration from David Beckham, enabled the Nerazurri to move nine points clear at the top of Serie A in the most dramatic circumstances.
Inter, who took the lead through Diego Milito after 10 minutes, finished the game with just nine men as tempers flared in the tumultuous atmosphere.
Wesley Sneijder was dismissed midway through the first half for dissent and then, after Goran Pandev grabbed the crucial second goal for Inter with a gorgeous free-kick, Lucio was sent off for handling Klaas-Jan Huntelaar's shot in the area in injury-time.
The numerical disadvantage hardly told, but Milan even missed the resulting penalty when Ronaldinho saw his spot-kick well saved by Julio Cesar.
Beckham was shown the first yellow card of the game for his second foul in the third minute and that early booking set a strict standard which referee Gianluca Rocchi was obliged to maintain.
The opening goal was inevitable and it came in the 10th minute from Inter's top goalscorer Milito.
Ignazio Abate played a half-hearted header back to his goalkeeper and Milito pounced on the ball, needing one touch to control it and another to place it into the only part of the goal Dida could not reach.
Lucio was shown a yellow card for simulation and Sneijder applauded the referee ironically, only he did not see the funny side, sending the Dutchman for an early bath in the 26th minute.
Pandev sealed the success when he found the back of the net in the 65th minute with a direct free-kick, but there was still 25 minutes to play down.
They defended resolutely before Rocchi sent the second Inter player off, showing Lucio a second yellow for a handball inside the penalty area.
However, Julio Cesar denied fellow Brazilian Ronaldinho as he pushed his penalty wide of the post as nine-man Inter held on for a win which takes them a step closer to the league title.
Meanwhile, Claudio Ranieri, sacked by Juventus just before the end of last season, got his revenge with a John Arne Riise-inspired 2-1 victory for Roma that could well seal the fate for his successor Ciro Ferrara.
Current Juve boss Ferrara's best chance of hanging on to his job could be club president Jean-Claude Blanc's reluctance to sack his manager after a defeat inflicted by the coach he sacked just eight months previously.
Roma, who are now 12 league games unbeaten, fell behind to Alessandro Del Piero's opener, but Francesco Totti equalised from the spot and Juventus then had 'keeper Gianluigi Buffon sent off for a foul outside the box on Riise.
That was the cue for a nervous final few minutes in which the Norwegian defender had the last word, heading in a 93rd-minute winner.
Elsewhere, Arjen Robben celebrated his 26th birthday with a man-of-the-match performance and a free-kick goal that was too much for Bayern Munich coach Louis van Gaal.
As Robben ran to celebrate with his coach in Bayern's 3-2 win away to Werder Bremen, Van Gaal slipped and fell on his back on the touchline. "It was a good job he only scored once," said the manager.