Juventus closed all talk of a challenge to their Serie A dominance after coming through a second-half onslaught at Napoli to win 2-1 in an engrossing match that saw each side have a man sent off and stretch their lead at the top to a huge 16 points.

Massimiliano Allegri's leaders have now as good as sealed their eighth straight Serie A title after a match that looked dead at half-time with Juve two goals and a man up but sparked back into life when goalscorer Miralem Pjanic was sent off for handling a Napoli pass and picking up a second yellow card just after the break.

"I fell asleep, I should have replaced Pjanic when he had the first card. He was at risk, but I didn't expect him to handle," said Allegri, whose future at Juve is uncertain after what will be five seasons in Turin.

"I already said we'll sit down to talk about this season and the next. I am very happy to be at Juventus."

Midfielder Pjanic swept home his free-kick opener in the 28th minute, which came immediately after Napoli were reduced to 10 men thanks to goalkeeper Alex Meret slicing down Cristiano Ronaldo after the Portuguese nipped in to intercept a terrible Kevin Malcuit backpass.

Emre Can looked to have sought the points for a dominant Juve when he added the second from a corner 11 minutes later after substitute David Ospina tipped away Pjanic's stinging shot but the Bosnian's red card gave Napoli a glimmer of hope.

They were back in the game in the 61st minute when Jose Callejon tapped home a pinpoint Lorenzo Insigne cross, and then piled the pressure on a suddenly creaking Juve, with Piotr Zielinski twice forcing fine saves from countryman Wojciech Szczesny.

It looked as though the hosts were set to launch a final assault when they were given a penalty six minutes before the end for a controversial handball decision against Alex Sandro given thanks to the video assistant referee system, only for Insigne to crash his spot-kick against the post and let the champions off the hook.

As elsewhere across Serie A this weekend, Fiorentina's game at Atalanta stopped in the 13th minute to honor the memory of deceased former Italy international Davide Astori, with fans of both sides applauding the ex-Fiorentina captain, who died in his sleep aged just 31 on March 4 last year. The hosts won the game 3-1.

Serie A results:

Napoli 1-2 Juventus

Atalanta 3-1 Fiorentina

Torino 3-0 Chievo

Genoa 0-0 Frosinone

SPAL 1-2 Sampdoria

Udinese 2-1 Bologna