Milan head coach Stefano Pioli claimed his side did not deserve to lose against Napoli, dismissing any suggestion the Rossoneri's fitness levels have dropped.

Napoli headed to San Siro having lost consecutive league games but were ahead inside five minutes when Eljif Elmas managed his first league goal since early November – Napoli scoring their quickest top-flight goal against Milan since November 2012.

Visiting goalkeeper David Ospina was rarely called upon in a somewhat sedate affair, though Franck Kessie saw a stoppage-time finish ruled out by VAR for offside against Olivier Giroud, who was on the floor in the build-up to the midfielder's opportunity.

Napoli held on for back-to-back league clean sheets against Milan for the first time since 2015, as Luciano Spalletti's team leapfrogged Milan to move into second on goal difference, the pair four points back from leaders Inter.

However, Pioli – without a win against Spalletti in nine league meetings – believes his side's performance did not warrant a loss as he refuted suggestions Milan might be flagging in terms of fitness.

"We are not tired, we proved it tonight [Sunday]," Pioli told DAZN. "Yes we can play with more quality, certainly, but we played a game from the point of view of intensity and energy among the best in the league.

"From a physical and willpower point of view, the team were pleasing in every way. We missed the last step.

"But there are the regrets, such as the goal conceded and the balls lost. We played almost always in the Napoli half, we played a real, serious and energetic game. We are lacking a bit of quality at the moment, but the team didn't deserve to lose. The data is very close in victories and defeats, the team had a balanced performance.

"The important numbers that we take into consideration are the acceleration and deceleration; the numbers are more or less those from the start of the season. The coach's eyes are also important, and the team didn't do badly tonight."

Pioli's team would have been heading into the final Serie A matchday of 2021, when they visit Empoli on Wednesday, in second place if Kessie's late strike had not been ruled out.

The Milan head coach, who was pictured by television cameras among the celebrations near Napoli's goal for the apparent equalizer, accepted the decision – but still expressed confusion as to how Giroud was adjudged to be involved in the play.

"I know that in the end they will say that the ruling is right, but I ask how does a player on the ground, who does nothing to intervene, how does he cause damage to the defender? Giroud does nothing to intervene," Pioli said.

"Now let's lick our wounds and try to do better for Wednesday."