Inter 3-2 Juve: Stankovic stars for Inter
Midfielder Dejan Stankovic was the star of the show as Inter Milan inflicted another painful defeat on out-of-sorts Juventus.
He set up the first, won a penalty for Inter's second goal, and then scored the decisive third himself as Inter beat a Juve side who had Uruguayan defender Paolo Montero sent off for a record 14th time in his Serie A career.
Like Juve, and perhaps more so, Inter have failed to match expectations this season.
They are sixth in Serie A and must keep winning until the end of the season to stand a chance of playing Champions League football next term.
With their superstars on form, they have a chance, but Inter have been frustratingly inconsistent this season.
They went ahead after six minutes of Sunday night's big match when Obafemi Martins converted from close range.
Stankovic burst into the area and squared the ball from his position just to the left of the penalty spot, with the young Nigerian clipping the ball over Gianluigi Buffon.
The own goal looked set to take the teams into the break on level terms, but a minute before the interval came Inter's second goal.
Stankovic surged into the area, this time to the right of goal, and had his progressed checked by a late challenge from Gianluca Zambrotta which referee Pierluigi Collina deemed worthy of a spot-kick.
Christian Vieri smashed the ball left-footed down the middle of the goal, rippling the net, to restore Inter's advantage.
When Inter went 3-1 up after just 90 seconds of the second half, it looked as though they might pile on the goals.
Francisco Farinos floated over a corner kick from the right side of the pitch, and with the Juventus defenders static, Ivan Cordoba flicked the ball on from his position at the near post.
Stankovic timed his run to perfection at the back post and sidefooted home from eight yards.
There had to be a Juventus response, and there was, but it was horribly ugly.
Montero's disciplinary record has always been a problem, and a wild challenge on Martins in front of the dug-outs earned him an early bath.
Inter pushed forward in search of a fourth goal and Giorgios Karagounis stung the palms of Buffon with a powerful 20-yard shot which the goalkeeper pushed out for a corner.
They were in charge, but a second Juve goal in the third minute of injury-time made the finale tense.
Enzo Maresca flighted a free-kick into the Inter penalty area and Marco Di Vaio's header beat Fontana.
There was to be no equalising goal, however, as Inter held firm until Collina's whistle.
Juve were disappointing, as they have been for much of the last month, and second place in Serie A may now be beyond the two-time defending champions.
They have fallen a point behind Roma, who occupy that second place and have a game in hand, with leaders AC Milan a further nine points better off.