TURIN, Italy (AFP) - Disgraced former Italian champions Juventus moved seven points clear at the top of Serie B after a 2-0 victory over Napoli on Tuesday.
The match was marred by clashes between rival supporters outside the Olympic Stadium ahead of the afternoon kick-off.
A fan was hospitalised after being stabbed in the leg.
The man was rushed to hospital but was not reported to be seriously injured, according to the Ansa news agency.
It was a sorry beginning to a match that had great significance in the promotion race as Napoli are one of Juve's main rivals.
Juventus dominated the early running and took the lead on 18 minutes as Italian midfielder Mauro Camoranesi headed home a cross from Czech counterpart Pavel Nedved despite a tight angle.
Camoranesi was involved again in the second goal as his cross was turned home by Juve captain Alessandro Del Piero four minutes after the break.
Juve were forced to hold on with 10 men after Claudio Marchision was sent-off on 62 minutes after throwing a punch at an opponent.
The league leaders survived without too many scares though and moved seven points clear of Genoa with Napoli a further two points back.
But the crowd trouble will have come as unwelcome news for Italian football which is already reeling from a flurry of recent incidents.
The Italian government last week passed new laws they hope will stamp out football hooliganism.
Strict new security measures were introduced shortly after a policeman was killed when Catania fans went on the rampage before, during and after their Serie A derby match against Sicilian rivals Palermo in February.
There was also trouble between Roma and Manchester United fans ahead of last week's Champions League quarter-final first leg tie with several United fans being stabbed before the game.
The government clampdown demanded clubs took more responsibilty for security, including more closed-circuit television (CCTV) cameras at stadiums, named tickets, electronic turnstiles, adequate stewarding, and crowd filtering areas outside grounds.
Juventus were last summer demoted from Serie A and given a nine-point handicap in Serie B for their role in the Italian match-fixing scandal.
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