A David Trezeguet hat-trick and two goals from Vincenzo Iaquinta gave Juventus a 5-1 home win over Livorno on their return to Serie A on Saturday.

France [Images] striker Trezeguet put Juve ahead after half an hour when he headed in Alessandro Del Piero's cross from close range.

Juventus, back in the top flight after their demotion last year for match-fixing, extended their lead midway through the second half when substitute Iaquinta converted a penalty after he was hauled down by defender Alessandro Grandoni.

Debutant Iaquinta, a close-season buy from Udinese, claimed a second late on when Pavel Nedved's rasping shot deflected off him and wrong-footed Livorno goalkeeper Marco Amelia.

Trezeguet, who fell out with club bosses following their promotion last season before surprisingly signing a new contract, then grabbed his second with a coolly-taken finish and netted a third with a back-heel almost on the goalline.

Massimo Loviso scored a consolation in injury time with a 20-metre drive.

The result slightly flattered a workmanlike Juve, who scored their last three goals in a frantic final five minutes, but Trezeguet was still thrilled.

"We have shown that we are back," he told Sky Sport. "Now we look ahead, but we have only taken one step even if it is important for confidence and morale."

LAZIO DRAW

Despite the scoreline, Claudio Ranieri's new signings have yet to gel and he sprang a surprise by giving midfielder Hasan Salihamidzic a league debut at right back.

Lazio and Torino earlier drew 2-2 in an entertaining opening to the Serie A season.

Alessandro Rosina's perfect chip over 43-year-old goalkeeper Marco Ballotta gave visiting Torino the lead in a first half in which three players went off with injuries, including Lazio defender Mobido Diakite with a broken leg.

Lazio, who visit Dinamo Bucharest in the second leg of their Champions League third qualifying round tie on Tuesday, equalised on 56 minutes through Goran Pandev with fellow striker Tommaso Rocchi putting last season's third-placed team 2-1 up.

Torino hit back on 68 minutes when the unmarked Tommaso Vailatti headed in at the far post and they held out after Gianluca Comotto was sent off late on for a second booking.

The rest of the first round of matches take place on Sunday with Inter Milan beginning their title defence at home to Udinese and last season's runners-up AS Roma travelling to Palermo. European champions AC Milan visit promoted Genoa.

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