Dries Mertens bagged a brace to intensify Sampdoria’s crisis, while Fernando Llorente provided an assist within minutes of his Napoli debut.
The Partenopei moved back to a 4-4-2 formation after two seven-goal thrillers in Florence and Turin, with Hirving ‘Chucky’ Lozano making his first start, as Arkadiusz Milik and Lorenzo Insigne were not fully fit, Kostas Manolas and Allan rested. Samp had lost both rounds going in and had Ronaldo Vieira suspended, with Gonzalo Maroni still injured, but gave Emiliano Rigoni his debut in a move to 3-4-1-2.
The Blucerchiati have now lost seven of their last eight Serie A meetings with Napoli and managed only two draws from 12 visits to the Stadio San Paolo since 1998.
The first real save was from Alex Meret, who showed cat-like reflexes to put up a hand and bat away Alex Ferrari’s attempt from point-blank range.
However, Napoli were moving it around better and took the lead within 13 minutes. It was a trademark passing switch from left to right, until Giovanni Di Lorenzo pulled it back across for the newly-blond Mertens to tap in from eight yards.
It was almost 2-0 moments later, with Eljif Elmas’ angled drive and a Lozano snapshot skimming the upright. It was wide open, as Mertens saw his curler from an improbable angle bounce off the underside of the bar and back out.
Within 30 seconds, Sampdoria had nearly equalised, as Rigoni pounced on a slip to go clear on goal, denied by Meret one-on-one.
Quagliarella turned on a sixpence for a shot that skimmed the upright, then blasted another dangerous attempt wide, but Lozano wreaked havoc every time he ran at defenders with the ball at his feet.
Eljif Elmas skipped past Jeison Murillo to force a tricky save at the near post, then fired another attempt over. Fernando Llorente made his Napoli debut and within 60 seconds had provided an assist for the second Mertens goal. It was at first disallowed for offside, but VAR confirmed the touch came off a Samp player when the Spaniard drew Audero out and pulled back for his Belgian teammate. It took Mertens to 112 competitive goals in a Napoli jersey.
Jose Callejon deserved a goal for his sensational right-foot volley, but Audero kept it out with an even better one-handed save under the bar from a tight angle.
Quagliarella continued to be the only Sampdoria threat with his own impressive volley that struck the side-netting. Substitute Manolo Gabbiadini flashed a dangerous ball across the six-yard box, Albin Ekdal getting his studs to it, but not enough to steer it on target from point-blank range.
Lorenzo Insigne came off the bench and curled inches wide, then forced another save from Audero with his cross-shot.
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