Lazio holds 10-man Juve to tough draw
The Bianconeri, who are targeting a third straight Scudetto win, have streaked clear of Roma at the top of the table by winning 12 games in a row but a 13th straight victory would elude them in the capital city.
Buffon, 35, appeared out of sorts in the early exchanges and soon left his team at a real disadvantage when fouling Miroslav Klose to concede the penalty gratefully converted by Antonio Candreva.
For a long time Lazio seemed destined to claim their third win in four games but Fernando Llorente denied them, sparing Juve's blushes with a clever header that sent one of the points back to Turin.
Lazio, who remain in ninth place, may look a much-improved unit under recently returned coach Edy Reja but unstoppable Juve were always going to provide the sternest of tests at the Stadio Olimpico.
Indeed within nine minutes Arturo Vidal had taken aim from outside the box, just steering the ball over the crossbar with Etrit Berisha struggling to cover its flight.
Lazio nearly found a way in against the run of play when Buffon fell over his own feet in front of the onrushing Klose, but the German could not covert and the chance was wasted.
The two men would renew their acquaintance in the 24th minute, and this time there was no let-off for Juve's keeper after he felled Klose in the area.
The exasperated Buffon was shown a straight red card and Candreva gladly stepped up to fire Lazio ahead against the Italian champions.
Without their talismanic stopper, who was replaced by Marco Storari as midfielder Kwadwo Asamoah was sacrificed, Juve suddenly seemed nervous and were restricted to one more decent effort before the break.
Llorente twisted to strike the ball with his left foot as it arrived in the area, but Berisha made an impressive double save to preserve Lazio's lead going into half-time.
Juve took a patient approach when play resumed and a counter-attacking move between Paul Pogba and Llorente failed to yield a positive result.
The Spaniard would be celebrating on the hour mark, though, as his classy header got the better of Berisha.
This time a raid organised by Carlos Tevez and Stephan Lichtsteiner saw the Swiss stand up a cross for Llorente, who swivelled his head to loop the ball over Lazio's keeper and into the far corner.
Tevez nearly made it 2-1 as Lazio regrouped, Berisha bravely punching his drive out for corner and with 17 minutes remaining Llorente came up just short on a neat pass from his Argentinian team-mate.
Storari had enjoyed a reasonably quiet night since answering Juve's emergency call but he soon proved his worth by keeping Klose out.
He did have a little help from the upright as he touched the German's close-range header to safety.
Substitute Balde Keita had only been on the pitch for two minutes when he gave Storari another scare, and Buffon's stand-in was definitely relieved to see the Spaniard shoot wide as Juve held onto a share of the points.
Information from The Associated Press was used in this report.