NAPLES, Italy -- — Runaway Serie A leader Napoli fell to only its second loss in the league when it was beaten 1-0 by Lazio on Friday.

Matías Vecino’s second-half strike was enough to hand the visitors the victory that lifted them into second spot in Serie A, a point above the Milan teams.

Napoli, nevertheless, has a 17-point advantage but could see it trimmed slightly if AC Milan wins at Fiorentina on Saturday or Inter Milan beats Lecce the following day.

Lazio’s first victory in Naples in almost eight years followed a high-intensity match at Stadio Diego Armando Maradona but with few concrete goalscoring opportunities. That was unsurprising as the teams have conceded the least in Serie A.

Lazio came closest to taking the lead in the fifth minute when Luis Alberto whipped in a free kick and Vecino’s header was headed off the line by Napoli defender Giovanni Di Lorenzo with goalkeeper Alex Meret beaten.

Napoli upped its game in the second half and should have broken the deadlock in the 58th minute when Di Lorenzo’s cross was backheeled on by Victor Osimhen but Piotr Zieliński drilled narrowly wide of the right upright.

Lazio went in front nine minutes later, during Napoli’s best period of the match. Napoli winger Khvicha Kvaratskhelia attempted to head clear a cross but the ball came to Vecino who hit a great strike into the ground and into the bottom left corner.

It was the first goal Napoli conceded in six matches in all competitions.

Napoli could have leveled 11 minutes from time but Osimhen — who had netted 11 goals in his previous 10 matches — headed Kvaratskhelia’s cross off the crossbar from point-blank range. Lazio goalkeeper Ivan Provedel then pulled off a stunning save to keep out a header from Kim Min-Jae on the rebound.

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