The Chilean struck early on from the penalty spot and doubled his tally in the first half, to open up an 11-point lead at the summit for the Old Lady
Arturo Vidal was the hero for the Bianconeri, netting twice in the first half during a routine win that leaves the Turin outfit 11 points clear at the summit with just six matches left.
After crashing out of the Champions League in comprehensive fashion against Bayern Munich, Juve were keen to put that disappointment behind them and continue their march to the title in the Italian capital.
Against a Lazio side still in the hunt for a spot in the continental competition, Antonio Conte's men could not have asked for a better start.
Just seven minutes into the encounter, Mirko Vucinic escaped Lorik Cana only to be cut down in the box by a clumsy tackle from the centre-back. There was no doubt whatsoever about the penalty decision, and Vidal fired home with authority and put his side into the lead.
The goal immediately put the visitors in the ascendancy, as Lazio struggled to contain a vibrant attack throughout the first half.
Michael Ciani came to the rescue of his side to block from Claudio Marchisio after the midfielder latched on to Stephan Lichtsteiner's cross, while Vucinic went close to netting as his toe-poke from a low free kick forced an instinctive save from Marchetti. The home side challenged across the pitch, but their offensive efforts lacked clarity and focus and they rarely threatened Gianluigi Buffon between the posts.
Ciani prevented what seemed to be a certain second goal when he made a diving intervention to block Vidal's shot, but Juventus were in control and it seemed just a matter of time before they would double their lead.
Minutes after that chance, Vucinic's pass took a somewhat fortunate deflection in the box and, as the Lazio defence hesitated, Vidal took full advantage as he coolly finished past Marchetti. The Biancocelesti were sinking without trace, and Champions League football looked a distant dream as they went into the break well behind the Serie A pace-setters.
A more determined home side came out for the second 45 minutes, and they nearly pulled one back just after the interval. A looping corner found the net of the stooping Ciani, and Buffon was forced to make an excellent save to keep his clean sheet intact as the ball spiralled towards the bottom-right corner. Moments later, however, Juve should have put the game beyond doubt with a golden chance.
Andrea Pirlo's free kick was saved by Marchetti, but the keeper could not hold on to the ball and it rolled loose with at least three black shirts chasing the rebound. Marchisio arrived first, but misjudged the bounce and off balance, sliced his shot well over to the bar. Lazio then lamented their luck in front of goal; with Miroslav Klose making a mess of a perfect cross from Antonio Candreva.
After a thrilling start to the second period, the match soon lost its urgency with Juventus taking control, stroking the ball around the park and assuring victory. There was no way back for the home team, who slumped to defeat in front of their own fans and saw their hopes of European football fade even further.
The win means Juve move 11 points clear of Napoli at the Serie A summit, and with just six games left to play, the title looks almost certain to return to Turin. Lazio, meanwhile, remain in fifth place, eight points behind AC Milan who currently occupy the final qualifying spot for the Champions League.