Lazio forward Daichi Kamada sealed his side’s 2-1 win at Napoli as the defending Serie A champions slipped to their first defeat of the season.

The Japan international struck early in the second half after Napoli captain Piotr Zielinski had cancelled out Luis Alberto’s opener before half-time.

Napoli, who finished last season 16 points clear of runners-up Lazio, spurned a hatful of chances after dominating the first half.

But the visitors were well disciplined at the back and always dangerous on the break as they secured their first win of the season.

Napoli made the better start as winger Khvicha Kvaratskhelia had two early shots blocked and Lazio goalkeeper Ivan Provedel saved twice from Mathias Olivera and Zielinski.

Victor Osimhen headed a scoring chance wide and Kvaratskhelia was denied by another smart Provedel save before Lazio struck against the run of play after half an hour.

Felipe Anderson’s pass inside the box found Luis Alberto and the Spanish midfielder finished with an impressive back-heel into the far corner.

Lazio’s Mattia Zaccagni, right, had a second-half effort ruled out by VAR

But Napoli’s response was almost immediate as Provedel was left helpless when Poland winger Zielinski’s drilled shot from outside the penalty was deflected past him two minutes later.

The home side continued to rack up the chances before the break, with Osimhen and Olivera both firing off target.

Provedel produced another fine save early in the second half, beating away Zielinski’s swerving volley before Lazio stunned the home fans at the Stadio Diego Armando Maradona with a second goal in the 52nd minute.

Felipe Anderson burst down the right on the counter and his cut-back to the edge of the area was dummied by Luis Alberto, allowing Japan forward Kamada to take one touch before burying a low finish.

Napoli looked to his straight back again and blocked shots from Kvaratskhelia and Stanislav Lobotka sandwiched another long-range effort from Zielinski.

Lazio caught their hosts out twice more on the break and the Napoli faithful breathed huge sighs of relief as two efforts from the visitors were ruled out for offside in the space of four minutes.

Mattia Zaccagni and debutant Matteo Guendouzi both thought they had made it 3-1 before VAR intervention spared Napoli, with the latter’s strike viewed by the referee on the pitchside monitor.

Luis Alberto went close to wrapping it up for Lazio when he curled a shot narrowly wide in the 85th minute.

Napoli applied late pressure, but failed to breach Lazio’s impressive defence and substitute Jesper Lindstrom blazed the ball high and wide when presented a chance in the closing stages.