This time, nobody walked. When the racist chants began at San Siro on Sunday evening, Mario Balotelli turned towards the offending supporters and pressed a finger to his lips. An announcement was broadcast over the stadium's public address warning that displays of discrimination – whether on the grounds of race, sex, religion or regional stereotypes – would not be tolerated. But in the short term, at least, Milan's match against Roma continued.

That had not been the case four months previously, when Kevin-Prince Boateng was abused during Milan's friendly against Pro Patria. Back then the midfielder simply kicked the ball in the direction of the culprits before removing his shirt and walking off the pitch. His team-mates followed suit, and the game was abandoned.

Boateng was acclaimed for his bravery, his stand described in the Italian newspaper La Repubblica as "the only just and reasonable act we have seen in decades of barbarised football". The player was invited to address United Nations delegates on the importance of confronting racism, as well as to meet with the Fifa president Sepp Blatter.

But it is one thing to walk out of a friendly on a point of principle, quite another to do it in a match that matters. Milan had gone into Sunday's game against Roma knowing that victory would allow them to tie up third place in Serie A once and for all. Anything less would mean travelling to Siena on the final weekend with qualification to next year's Champions League still very much in jeopardy.

So when a section of Roma's supporters began to make monkey noises at Boateng and Balotelli on Sunday, both players knew that there was little they could do in response. As Blatter himself had reminded the club back in January, teams that abandon games will typically be made to forfeit them.

Under Fifa's guidelines, only the referee should decide when a match needs to be suspended. Gianluca Rocchi was the man filling that role on Sunday. His selection for this game had been a controversial one. Rocchi hails from Florence, home to the Fiorentina team that has been challenging Milan for that last Champions League berth.

At first Rocchi did not act. When the chants began mid-way through the first half, he allowed play to continue. It was, as ever, a vocal minority leading the abuse, and many supporters in both the home and away sections attempted at first to drown them out with jeers and whistles.

The voice on the PA warned twice that the game could be suspended, but it was not until after the interval that Rocchi made good on that threat. In the 48th minute the referee brought proceedings to a halt, scooping the ball up and tucking it under his left arm. As he did so, Roma's captain, Francesco Totti, went over to address the troublemakers. The game was suspended for a total of 97 seconds before the chants died down and play resumed.

Sadly, that was not to be the end of it. Further monkey noises were heard on at least two more occasions before the end of the game. Some Milan supporters responded with a chant of "Nerone, bruciali tutti!". That phrase would commonly be translated as "Nero, burn them all!" – a reference to the emperor who was accused of playing his lyre while Rome burned in the Great Fire of 64 AD. But this was likely a deliberate play on words. "Nerone" can also mean "big black".

It all added up to a deeply dispiriting scene. "What a beautiful evening for families," wrote a bitterly sarcastic Alessandra Bocci in Monday morning's Gazzetta dello Sport. The Milan manager Massimiliano Allegri lamented the "retrograde mentality" displayed by his compatriots.

This, after all, was no isolated incident. In just the last few weeks Balotelli had been racially abused during away games against Juventus and Fiorentina (and he wasn't even playing against the former). Such instances not only stain the reputation of the league, but also deter families who might otherwise consider bringing their kids to a game – with the result that stadiums become both ever more empty and dominated by the extremist fringe.

These problems are not new. Racist chants and banners have been a feature of Italian stadiums for decades. Endless initiatives have been launched to combat such activity, from public awareness campaigns to a system of fines for clubs whose fans persist in racist chanting. The Italian Football Federation has recently sought to refine the latter method, offering discounts to teams if they can identify ringleaders and ban them from the stadium.

Players have staged their own protests. Marco Zoro walked off the pitch after being abused during Messina's game against Internazionale in 2005, before eventually being persuaded to continue. In 2001 Treviso's players and manager famously "blacked up" in support of their forward Akeem Omolade.

The truth is that there can be no simple solution to a complex problem. Racism persists in Italian stadiums in part because it persists in sections of Italian society. A culture of campanilismo – the sense of belonging to one's town or province, rather than to the country as a whole – has tended to foster wariness in some communities towards all outsiders, not just those with a different skin colour, religion or nationality.

It is also true that the perpetrators of racist chants will often seek to defend their actions with the claim that they are not racist at all – but simply intent on doing whatever it takes to get under an opponent's skin. Not all of the chants aimed at Balotelli on Sunday, for example, were explicitly racist. At times he was simply informed: "You must die. You must die."

To his credit, Balotelli managed for the most part to keep his cool. That was more than could be said for his team-mate Sulley Muntari – sent off after attempting to physically restrain the referee.

It all began with a foul by Balotelli. The forward arrived late, if not with any particular malice, into a challenge on Marquinho in the 39th minute, and was duly booked for his trouble. Muntari protested on his team-mate's behalf, and got shown the yellow card too. At that point he got into in a physical confrontation with Rocchi, leading the referee to reach for the red.

Rather than accepting his fate, Muntari then proceeded to grab Rocchi's arms, restraining them by his side. For about half a minute he prevented the official from getting the card out of his pocket. As a long-term strategy, though, his approach had its flaws. Eventually Rocchi obtained the card and sent Muntari off. The player's ban is likely to be a long one.

In the short term Muntari seemed to have put his team in a perilous position. Roma had started the game brightly, and this was a fixture that they too needed to win in order to maintain their faint hopes of qualifying for Europe through the league.

Despite such stakes, however, there was a lack of urgency on both sides. A game which had promised much during its high-tempo opening exchanges petered out into a tame goalless draw. The second half was notable only for Totti getting himself sent off in injury time, for an elbow to his former team-mate Philippe Mexès.

The good news for Roma fans is that suspensions in Italy do not carry over from one competition to another, meaning that Totti will still be available for their Coppa Italia final against Lazio in two weeks' time. If Roma do not win that game, they will not play in Europe next season.

As for Milan, their Champions League fate will be determined by the aforementioned trip to Siena. Their task is made easier by the fact that these opponents have nothing left to fight for after their relegation was confirmed last week. On the other hand, Siena have been hard to break down at home, conceding less than one goal per game.

Allegri will hope Balotelli can recapture the form that has helped Milan score nine in their previous three games. Most other fans of Italian football will simply hope that we can finish next week talking about things that happened on the pitch, not off it.

Talking points

• It would be remiss of me to discuss Milan's performance this week without making reference to that kit, the golden monstrosity which will serve as their third strip next year. In fact it is intended to be their European kit, something which they rather clumsily revealed by having players pose in a version bearing the Champions League badge – even though they have not qualified for it yet. Their oversight was noted by the Fiorentina manager Vincenzo Montella, who suggested at his pre-game press conference on Saturday that his team were using it as additional motivation. The Milan vice-president Adriano Galliani later replied: "It was a simple mistake which somebody with nothing better to do tried to make a story out of. To try to read something into that is deranged."

• One further subtext to Sunday night's game was to be found in the contest between the two managers. Aurelio Andreazzoli has served as Roma's caretaker since Zdenek Zeman was fired in February, but despite achieving respectable results he does not seem to be a popular choice among the club's directors to fill the role on a permanent basis. They have instead been linked consistently in recent weeks with a move for either Milan's Allegri or Napoli's Walter Mazzarri. "It will be the club who decides my future – just as it was when they called on me in the first place," insisted Andreazzoli, somewhat grumpily, on Sunday evening.

• Muntari's attempts to restrain Rocchi got me to wondering whether any other players had attempted to physically prevent a referee from showing a card. The answer was yes. I present to you Madjid Bougherra in an Old Firm derby and, of course, John Terry for Chelsea against Manchester United. I'm sure there must be more, so if you know of any then do post them below the line.

• On Saturday Gigi Buffon picked up a Serie A winner's medal at Juventus's Scudetto celebration in Turin. On Sunday he saw the team he owns, Carrarese, get relegated from the first division of the Lega Pro. A childhood fan of the team, Buffon nevertheless did not shy away from going to meet with supporters afterwards to answer their concerns about the club's future.

• Juve can no longer break their record points tally in Serie A, after drawing 1-1 with Cagliari in Turin. Victor Ibarbo ran the length of the field to score for the Sardinians, but you have to wonder whether Buffon would have kept his shot out had he been on the pitch.

• Has Edinson Cavani played his last home game for Napoli? Only time will tell on that front, though one group of Napoli supporters made their feelings clear by placing a cardboard cut-out of the striker in a cage last week (before thoughtfully leaving some food out for it). If this is indeed to be the last they see of the Matador, then at least he went out on a high, scoring in a 2-1 win over Siena.

• Palermo have been relegated to Serie B after losing 1-0 away to Fiorentina. The man who sealed their fate was none other than Luca Toni, a player who had helped them to reach the top-flight in the first place, scoring 30 goals for Palermo during their promotion season of 2003-04. (And then another 20 in Serie A the following year.)

• Parma celebrated the 20th anniversary of their first-ever European trophy on Sunday, inviting all the players who helped them to lift the Cup-Winners' Cup at Wembley in May 1993 back to the Stadio Tardini. As cool as it was to see Tomas Brolin and the gang reunited, my favourite photo of the afternoon was the one of the fans' pre-game coreografia. Parma's supporters held up banners showing the name of every player who started the final … in formation.

• Watching Antonio Di Natale leave Udinese's game against Atalanta on a stretcher, some fans might have worried that the striker had suffered the injury which would end his career. Instead, Di Natale suggested later that evening that he could even play next weekend against Inter. If not he will just have to settle for finishing this season on 22 goals. Not bad for a 35-year-old.

Results: Catania 1-0 Pescara, Chievo 1-1 Torino, Fiorentina 1-0 Palermo, Genoa 0-0 Inter, Juventus 1-1 Cagliari, Lazio 2-0 Sampdoria, Milan 0-0 Roma, Napoli 2-1 Siena, Parma 0-2 Bologna, Udinese 2-1 Atalanta.

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