Pavel Nedved headed the title-holders in front in first-half stoppage time before a three-goal salvo in six minutes brought Roma's three-match winning run to an abrupt end.

Zlatan Ibrahimovic's clinical right-footed strike gave Juve a two-goal cushion and two close range finishes from French striker David Trezeguet piled on the misery for sorry Roma.

Juve's French defender Lilian Thuram was then sent off for a professional foul on Vincenzo Montella and Francesco Totti rammed home the resulting penalty that was of little consolation to the 2001 champions.

Roma had dominated the first half but they failed to apply the finishing touch to some promising moves.

The end of the match was marred by clashes between Juve fans and police but order was quickly restored.

Juventus, who won their first nine matches, have 33 points from their 12 games played, followed by AC Milan on 28 and Fiorentina on 25. Fiorentina and AC Milan meet in Florence on Sunday.

Roma remain in sixth position on 18 points.

In Saturday's early match a headed goal in the 87th minute from Brazilian Felipe gave Udinese a 1-0 win at home to struggling Sicilian side Messina.

Ibrahimovic chose a well-known Italian phrase to express his joy after scoring Juve's crucial second goal.

The fixture is steeped in animosity since their infamous title scrap 25 years ago and Ibrahimovic stoked up their rivalry by accusing Roma of being worse than Serie A strugglers Ascoli.

Totti began the war of words by saying Juve coach Fabio Capello, who left Roma last year after insisting he could never work for the Turin club, was not a real man for going back on his word.

The home side suffused confidence in a frantic opening with Montella firing two shots straight at Christian Abbiati in the first seven minutes.

But they breathed a sigh of relief moments later when Trezeguet raced on to Emerson's pass only to see his angled shot blocked by Alexander Doni's shins.

Roma regained the initiative with Rodrigo Taddei's shot parried by Abbiati and Daniele De Rossi heading narrowly over the bar.

Abbiati saved at Montella's feet before Juventus took the lead second before the break.

Mauro Camoranesi was allowed time to cross from the right to the back post and Nedved rose above a static Christian Panucci to plant a firm header into the opposite corner.

Ibrahimovic outpaced Sammy Kuffour before prodding past Doni in the 56th minute and Trezeguet made it 3-0 with a firm header from Mauro Camoranesi's right-wing cross.

Trezeguet tapped in Ibrahimovic's cross as Roma's defence crumbled before Totti stemmed the tide from the penalty spot.

The two teams became bitter rivals after the 1980-81 season when Juve snatched the championship away from Roma thanks largely to a controversial refereeing decision.