Arkadiusz Milik’s opener was cancelled out by Jasmin Kurtic, as SPAL stopped Napoli closing on the top three with a surprise stalemate.
The Partenopei were fresh from a 3-2 thriller at RB Salzburg in the Champions League and made changes, bringing Lorenzo Insigne, Arkadiusz Milik and Eljif Elmas in, but Kostas Manolas, Nikola Maksimovic, Mario Rui and Elseid Hysaj were still carrying injuries. SPAL sat in penultimate place, but all their points were earned at home. Federico Di Francesco, Marco D’Alessandro, Marko Jankovic and Mohamed Fares were still injured.
It was a sparkling start for SPAL, as Francesco Vicari scuffed his finish from close range, allowing Kalidou Koulibaly to recover, then Andrea Petagna curled a free kick on to the crossbar with David Ospina beaten.
However, Napoli broke through with a left-foot daisy-cutter from 20 metres out, as Arek Milik found the near bottom corner.
Etrit Berisha had to rush off his line to tackle Milik outside the box, but SPAL continued their strong performance and pulled level.
Gabriel Strefezza got away down the right and pulled back to just inside the penalty area, where Jasmin Kurtic had made the run to fire home relatively undisturbed.
Napoli were awarded a penalty on 39 minutes for Francesco Vicari’s handball, however, it was revoked when viewed again on the VAR monitor. Mertens had flicked the ball on to the hand from point-blank range and the arm was flush with the torso.
SPAL nearly took the lead after the restart, as only a spectacular David Ospina save and goal-line technology confirmed Vicari’s glancing header from a corner hadn’t crossed over completely.
The hosts continued to pour forward, but Fabian Ruiz came off the bench and immediately saw his long-range strike deflected inches over the bar.
There were more worrying scenes for Napoli, because Kevin Malcuit fell awkwardly and seemed to sprain his knee. He hobbled off in tears.
Milik ran on to a smart Allan through ball, but Vicari timed the tackle perfectly to get a toe to the finish.
Fabian Ruiz thought he’d put Napoli in front again on 74 minutes, but his ferocious strike on an Insigne pull-back bounced off the base of the upright.
Fernando Llorente had the chance to win it deep into stoppages, but incredibly turned the free header over from a Milik assist.
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