But the leaders were given a real examination by eighth-placed Lazio, who have now lost nine of their last 10 Serie A matches against the Turin side.

Lazio were totally dominant in a first half which saw Juve fail to register a single attempt at goal, while the hosts forced Wojciech Szczesny into five saves before the break.

The Polish goalkeeper was relatively untroubled by a Wallace header after 13 minutes and dived down low to hold Joaquin Correa's strike six minutes later.

But the Biancocelesti kept piling on the pressure, with Spaniard Luis Alberto proving a particular threat.

The winger had an effort well kept out by Szczesny before teeing up Marco Parolo, who forced the best save of the half with a curling strike from 15 yards.

Just before the break, Juve centre-back Daniele Rugani almost gifted Lazio the lead as his header back to Szczesny was picked up by Ciro Immobile but the striker's lob over the keeper was hooked away by a recovering Rugani.

Alberto came close again after the interval, curling just wide of the right post from 20 yards.

Juve began to push forward and offer an attacking threat but failed to fashion any significant chances from their possession in the final third.

And Lazio deservedly took the lead after 58 minutes through an own goal. Alberto's corner was flicked on at the near post by Bastos and cannoned off the head of Can into the far corner.

Simone Inzaghi's side ought to have been two goals up after 67 minutes as Correa set Immobile clean through but Lazio's top scorer curled over the bar.

The response from the runaway league leaders was failing to materialise and Lazio's dominance continued, Alberto firing inches wide again before Sergej Milinkovic-Savic also went close.

But Lazio were made to pay for failing to bury their chances as Juventus equalised entirely against the run of play after 74 minutes.

Federico Bernardeschi drove down the left and cut back for Paulo Dybala, who notched Juve's first shot on target which was parried by Thomas Strakosha, but Cancelo was on hand to stroke in.

And four minutes from time Cancelo was pulled back in the area by Senad Lulic, with VAR ultimately awarding the penalty which was slammed into the roof of the net by Ronaldo.

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