Rome - The mayor of Milan said on Thursday he was ashamed of the racist chants directed at Senegal defender Kalidou Koulibaly during Wednesday's Serie A match between Inter and Napoli at the San Siro.
Sala also asked the Napoli player for forgiveness on behalf of the city of Milan.
The 27-year-old had been subjected to monkey noises from home supporters throughout the match. He was later sent off as Inter won the game 1-0.
Victory, though, was overshadowed by the chanting.
"The boos aimed at Koulibaly were shameful," said Sala on Facebook.
"A shameful act towards a true athlete who wears the colour of his skin with pride."
The mayor, who was at the San Siro for the match, said he would continue to go to games but would not tolerate any racist chanting.
"I will continue to watch Inter but at the first chant I will make a small gesture. I will get up and leave. I will do it for myself, aware that whoever abuses a black athlete won't give a damn about me," said Sala.
"I apologise to Kalidou Koulibaly on my own behalf and on behalf of the people of Milan who testify to feeling that we are brothers even in these difficult times."
Napoli coach Carlo Ancelotti revealed that the Napoli staff had asked the referee three times to suspend the match because of the chants.
"The solution exists," Ancelotti told Sky. "You have to stop the match. You just have to know when, after how many announcements. And if we don't know, then next time we may have to stop play ourselves."
Koulibaly apologised on Twitter for the defeat and being sent off but said: "I am proud of the colour of my skin. (Proud) to be French, Senegalese, Neapolitan: a man."