The winner came courtesy of a reliable source eight minutes from time as substitute Alessandro Del Piero curled in a free-kick from 25 yards.
Juve completely dominated the first half, but went to the dressing rooms with no lead to show for it.
But on the 30-minute mark the game broke free as Juve opened the scoring with a wonderful goal it. Andrea Pirlo clipped a clever pass over the defence for Pepe, who had missed a one-on-one moments earlier. He broke the offside trap with ease, and with his back to goal controlled the ball on his chest and hit an overhead past Federico Marchetti, who had no time to react.
A minute later Arturo Vidal almost scored from well behind the halfway line as he spotted Marchetti miles off his line. The keeper was quick to scurry back though and he tipped the effort over the bar.
Lazio just had no time to breathe as moments later Quagliarella turned his man in the area and forced Marchetti into an instinctive save as the ball almost looped over him.
On 38 minutes Quagliarella again almost doubled Juve’s lead after another fantastic Pirlo pass in the build up, but Mobido Diakite slid in just in time to divert for a corner.
Lazio had not had a sniff, but on the stroke of half-time they silenced the home faithful. The ball was whipped in from the right and Mauri leaped to plant a header into the top right corner, leaving Gianluigi Buffon with no chance.
The second half was a much tighter affair and Lazio did a much better job of frustrating the home side.
Mirko Vucinic put a shot just past the far post from a tight angle after 52 minutes, Stephan Lichtsteiner decided to go for glory with team-mates in much better positions halfway through the period, and later just failed to put the ball on a plate for Chiellini.
In the end the script seemed written as just eight minutes after coming on, Del Piero left Marchetti flat footed as he bent the free-kick past the wall and into the far corner.
There was still time for Lazio substitute Libor Kozak to pick up two yellow cards and receive his marching orders in the last 10 minutes.