Napoli say they find it “astonishing” that Italy defender Francesco Acerbi was not sanctioned over allegations of racism against their player Juan Jesus.

Inter Milan’s Acerbi was implicated by his opponent in the closing stages of a 1-1 draw earlier this month, with Jesus briefly pausing the match to report the matter to the referee.

But Acerbi will face no further action after defender Jesus’ claims were dismissed by a Serie A sports judge due to a lack of evidence.

In a statement, Napoli said: “The principle of the greatest likelihood of an event, which exists in sports justice and which appears clear from the dynamics of the incident and the apology offered on the pitch, simply vanishes in this judgement.

“We find it astonishing.

“If what happened on the pitch ‘is certainly compatible with the expression of offensive comments (…) by the Inter player, who does not deny that they were offensive and threatening,’ then why was Acerbi not sanctioned in any way?

“If, as the judgement itself reads, ‘there was certainly proof of an insult,’ why did the sports judge decide to take no action to punish the responsible party?

“We find that even more astonishing.

“Napoli will no longer take part in anti-racism and anti-discrimination initiatives run by football institutions that are merely symbolic, but we will continue to organise them ourselves, as we have always done, with renewed conviction and determination.”

Acerbi protested his innocence but agreed to withdraw from the national squad for this week’s games against Venezuela and Ecuador after discussing the matter with manager Luciano Spalletti.

Serie A sports judge Gerardo Mastrandrea considered the case against Acerbi, speaking to both men, others present on the pitch and also consulting recordings of the incident, but found insufficient proof to support Jesus’ own testimony.

Acerbi, who faced potentially serious sanctions had he been found guilty, has been cleared to turn out again for Inter when their league schedule resumes on April 1.

Mastrandrea’s ruling concluded: “In this case the minimum level of reasonable certainty regarding the discriminatory content of the offence committed is not reached.

“Without calling into question the good faith of the Napoli player, it appears to have been perceived only by ‘offended’ footballer without the support of any external evidence, be it audio, video or even testimonial.

“Discriminatory conduct, due to its intrinsic severity and intolerability, especially when it refers to the person’s race, skin colour or religion, must be sanctioned with the utmost severity in accordance with the Code of Sports Justice and the rules international sporting events.

“But it is nevertheless necessary that the imposition of such burdensome sanctions is correspondingly assisted by a minimum amount of evidence, or at least by serious, precise and consistent evidence in order to achieve reasonable certainty.”