Ciro Immobile equalled the all-time Serie A record of 36 goals, set by Gonzalo Higuain in this stadium, but Lazio lost 3-1 to Napoli and finished the season fourth.
The Biancocelesti could still technically get second place if they won here and Atalanta-Inter ended in a draw, but the main focus was on getting the all-time Serie A record for Immobile. He went into the final round on 35 goals, one shy of the 36 set by Gonzalo Higuain for Napoli in this stadium in May 2016.
Joaquin Correa had the ball in the net after five minutes, but play was halted for an earlier Sergej Milinkovic-Savic foul on Mario Rui.
It was the hosts who took the lead instead, as Fabian Ruiz saw his left-foot curler from the D take a deflection off Luiz Felipe, giving the ball that extra spin to loop around Thomas Strakosha’s fingertips into the far top corner.
Moments later, Luiz Felipe had to make a decisive block on Giovanni Di Lorenzo, then Lorenzo Insigne’s angled drive shaved a coat of paint off the base of the far post.
However, Immobile got the goal he needed to equal the all-time Serie A record of 36 in a single season. He sprung the offside trap and anticipated everyone to prod in the Adam Marusic roll across from the left after good work from Marco Parolo.
It remained wide open, Mario Rui’s curler flashing inches wide of the far post. After the restart, Mertens was about to fire in when Marco Parolo came lunging across with a sliding tackle and the referee pointed to the spot. Insigne stepped up to leave Strakosha stranded and restore Napoli’s lead.
Lazio fought back, Tucu Correa riding three tackles only to hit the upright from point-blank range. Luis Alberto went on a strong run to send Correa clear, but Ospina rushed off his line to narrow the angle.
This was Jose Callejon’s last game at the Stadio San Paolo and he was wearing the captain’s armband, but couldn’t score when his acrobatic volley flashed just wide on the Mertens assist.
Adam Marusic really should’ve equalised when allowed a free header at the back post, but he turned the Manuel Lazzari cross wide.
There were emotional scenes in the final stages, as first Callejon received hugs from everyone for his final match at the Stadio San Paolo, but then Insigne pulled up with a muscular problem and was utterly distraught, knowing Napoli face Barcelona in the Champions League next week.
The Partenopei still added a third goal in stoppages, Matteo Politano sweeping the finish at the near post after a Mertens one-touch assist.
It was an ill-tempered game that descended into a series of rows throughout the second half, including between the two coaches, and erupted in the final moments with Eljif Elmas and Sergej Milinkovic-Savic.
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