It was his first Champions League triumph as a coach, for AC Milan against his former club Juventus, whose fans had rejected him by daubing graffiti in the centre of Turin that read: 'A pig can't coach'.
Ancelotti recounts the 2003 final colourfully in his book, The Beautiful Games of an Ordinary Genius - from the motivational video he made by clipping together Milan highlights with the Al Pacino speech from the American football film Any Given Sunday, to the appearance of owner Silvio Berlusconi on the team bus.
Oh what a night: Ancelotti (centre left) celebrates with his 2003 champions, Milan
It was Andriy Shevchenko, who would later become an expensive Chelsea flop, who struck Milan's winning penalty after a dull and goalless 120 minutes.
'It was incredible to see the entire Juventus end of the stands motionless,' recalled Ancelotti. 'It looked like a poster. I wanted to take it off the wall and carry it home with me. What enormous satisfaction.'
The Milan team took the trophy back to the Worsley Park hotel where they then, according to Ancelotti, got 'completely snookered on English beer' before launching into an impromptu game of barefoot football on the 18th green of the hotel's golf course.
Video: Ancelotti's inspiration for his 2003 triumph - Al Pacino in Any Given Sunday
'We were the masters of all Europe and for that one magical night we were the masters of Manchester as well,' said Ancelotti.
Now at Chelsea and with his job under threat if they lose at Old Trafford, the Italian could use a repeat.
Meanwhile, Chelsea striker Daniel Sturridge has warned Ancelotti to play him or sell him, having been a revelation at Bolton since his loan move in January, scoring six goals in eight games.
'If I can play first-team football at Chelsea then great, but I don't really want to be on the bench,' he said. 'It's difficult coming in and playing the odd game for Chelsea because there's a lot of pressure.'
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Explore more:People: Silvio Berlusconi, Andriy Shevchenko, Carlo Ancelotti, Daniel Sturridge, Al Pacino Places: Milan, Manchester, Europe