Lazio face the prospect of playing their next two Serie A games with part of the Stadio Olimpico closed after racist chanting overshadowed their 2-0 defeat to Napoli on Wednesday night.
The Serie A fixture had to be stopped for several minutes by the referee after Lazio fans constantly barracked Napoli defender Kalidou Koulibaly with racial taunts and monkey noises.
"The situation was becoming embarrassing, for Koulibaly and for everybody," Napoli coach Maurizio Sarri said.
He praised referee Massimiliano Irrati for intervening, adding: "He did well to suspend play. [Koulibaly] is an intelligent, level-headed person. He's disappointed, but he's serene."
For three minutes, the match was paused, and an announcement was made warning that it would be abandoned in the event of further incidents of racism, but there were no further interruptions.
Lazio may now be forced to play their next two Serie A games with the area of the stadium where the racist chants were being made -- the Curva Nord -- closed, according to articles 11 and 18 of the Italian Football Association's (FIGC) rules of the game.
Hellas Verona were given a similar punishment last season, although it was reduced to a one-game suspended sentence on appeal after the club successfully contested that the alleged racist chants, purported to have been made by 3,000 fans, could not be distinguished sufficiently.
Since Irrati halted play on Wednesday night, and the racial chants are audible on videos taken within the stadium, Lazio would appear to be unlikely to succeed with a similar appeal.
Lazio's fans have already been punished numerous times for racial behaviour. In 2013, they were charged four times by UEFA for racial offences during their Europa League fixtures with Tottenham Hotspur (home and away), Maribor and Borussia Monchengladbach, and they were forced to play two European games behind closed doors.
In October of the same year, they were given another one-game stadium closure by UEFA "for a number of offences including racist chanting."
In August, their Champions League playoff match against Bayer Leverkusen was almost halted by referee Jonas Eriksson due to racist chants aimed at Leverkusen trio Jonathan Tah, Wendell and Karim Bellarabi, but they escaped punishment on that occasion.
Lazio coach Stefano Pioli, though, said stopping play on Wednesday night was not the right thing to do.
"If I had been the referee, I would not have stopped the game," he said. "Those chants should not be heard and there is no justifying it, but we've also got black players and they are respected.
"If we do this then you make a minority of people feel important. I would have let play continue."
Lazio's fans were also punished for racist insults towards M'Baye Niang and Edenilson in a Serie A fixture against Genoa a year ago, but their Nigerian midfielder Ogenyi Onazi says he does not notice them.
"When I am on the field, I don't hear what they are saying off it," he said. "Our fans are not racist, it's impossible."
3 punti importantissimi!Domenica un San Paolo da brivido ragazzi!Ma anche un San Paolo rispettoso!��esempio per tutti pic.twitter.com/RjcbcGYUMT
- Pepe Reina (@PReina25) February 3, 2016
Napoli goalkeeper Pepe Reina posted a picture of Koulibaly on Twitter and called for a "Stadio San Paolo which sends shivers down our spine on Sunday" against Carpi but added that it must also be "a respectful San Paolo."
He asked the Napoli fans to "set an example for everybody."