Napoli put on a five-star performance to crush Cagliari 5-0 on Monday and provisionally move four points clear at the top of Serie A.
VAR and a lack of it made for a chaotic start and end to the first half, but Napoli’s Magic Rectangle all got on the scoresheet, before Mario Rui completed the rout with a delightful free kick.
Only long-term casualty Faouzi Ghoulam was missing at left-back for the visitors, with Mario Rui staying on in his place ahead of new recruit Hrvoje Milic.
Cagliari, meanwhile, handed a first start of the season to Kwang-Song Han, the North Korean sensation who had returned from a loan spell at Perugia and was linked with Juventus last month.
The Partenopei were unbeaten in their last 15 League meetings with the Sardinians, whose most recent win came in April 2009.
An early chance fell to Mertens, who poked wide from close range, but Napoli should've been awarded a penalty and the VAR consulted as the Belgian's shirt was clearly pulled by Charalampos Lykogiannis.
Nonetheless, the Partenopei dusted themselves down and took the lead, when Allan's cutback was angled into the bottom-left corner of Alessio Cragno's net by Callejon.
Just three minutes before the break, Mertens was on hand to knock in Elseid Hysaj's low cross, although the VAR was strangely needed for the goal's veracity.
Cagliari, to their credit, weren't pushovers and had chances to socre themselves, only for ex-Napoli striker Leonardo Pavoletti to misfire twice and Pepe Reina to smother Han's one-on-one.
However, their enthusiasm waned after the restart and the Partenopei promptly pounced as Marek Hamsik struck home his side’s third goal on the hour mark.
Leandro Castan then illegally raised his arm to block a shot in the box, gifting Insigne the chance to dispatch a penalty into Cragno’s bottom right.
The game was seemingly dead and buried going into injury time, yet there was still time for a bolt from the blue, when Mario Rui bent in a beautiful free kick.
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