Striker Romelu Lukaku says "we are going backwards" on racism after he was racially abused by Cagliari fans while playing for Inter Milan on Sunday.
It follows incidents where Manchester United's Paul Pogba and Marcus Rashford, and Chelsea striker Tammy Abraham were abused on social media.
"As players we need to unify and make a statement on this matter," Lukaku said.
Cagliari said they were committed to "annihilating one of the worst plagues that affects football and our world".
In a statement the club, whose fans have been involved in a number of racist incidents, said they were in "full solidarity" with Lukaku and pledged to "identify, isolate and ban" the "ignorant individuals whose shameful actions and behaviours are completely against" the club's values.
Serie A - which expressed "firm condemnation" of the incident - is investigating the racist abuse, which came when Lukaku scored the winning goal in a 2-1 away victory.
After scoring a 72nd-minute penalty the former Manchester United striker stood and stared at fans behind the goal - where monkey chants had come from.
"Many players in the last month have suffered from racial abuse… I did yesterday too," Lukaku in his statement.
"Football is a game to be enjoyed and we shouldn't accept any form of discrimination that will put our game in shame.
"Ladies and gentlemen it's 2019 - instead of going forwards we're going backwards.
"I hope the football federations all over the world react strongly on all cases of discrimination.
"Social media platforms (Instagram, Twitter, Facebook) need to work better as well with football clubs because every day you see at least a racist comment under a post of a person of colour. We've been saying it for years and still no action."
Lukaku's former United team-mates Pogba and Rashford were both targeted on social media after penalty misses this season.
Chelsea defender Kurt Zouma was racially abused on Saturday after an own goal against Sheffield United, while team-mate Abraham and Reading's Yakou Meite both received racist messages online after missing penalties last month.
England women's manager Phil Neville said footballers should "boycott" social media and Chelsea boss Frank Lampard said social media companies needed to do more.
Last month, Twitter said it would meet clubs and campaigning organisations to show the "proactive work" being done to tackle abuse.
Past incidents at Cagliari
The abuse of Lukaku was the latest incident in which a black player has been racially abused on the pitch by Cagliari fans, prompting calls for action to be taken.
It was mentioned by Italian media but did not make the front pages of any of the three main sporting newspapers.
Last season Everton's Moise Kean suffered similar abuse when playing against Cagliari for Juventus.
Serie A decided not to sanction Cagliari for their fans' racism - despite admitting their actions were "reprehensible".
The previous year Cagliari fans were called out after abusing another Juventus player, Blaise Matuidi - but Italian football chiefs did not take any action.
In 2017, Pescara midfielder Sulley Muntari walked off the pitch after being racially abused by Cagliari fans - but was subsequently banned by football authorities for his protest.
Cagliari statement in full
Cagliari Calcio firmly rejects what happened Sunday night at the Sardegna Arena during the game v Inter Milan.
The club underlines - once again - its intention to identify, isolate and ban those ignorant individuals whose shameful actions and behaviours are completely against those values that Cagliari Calcio strongly promotes in all their initiatives. Every single day.
Cagliari v Inter Milan was the right occasion to appreciate and enjoy positive cheer, never addressed against anybody: in fact inside our "Curva Futura" - the first dedicated sector in Italy built to host children - both Inter Milan and Cagliari supporters enjoyed a lovely evening together in the name of their passion for football.
Cagliari Calcio does not want to underplay what occurred last night, endorses the respectable moral values of its people from all the stadium sections, but firmly rejects the outrageous charge and silly stereotypes addressed to Cagliari supporters and the Sardinian people, which are absolutely unacceptable.
Full solidarity to Romelu Lukaku and even stronger commitment toward annihilating one of the worst plagues that affects football and our world in general.
However, as we are aware that technology is not enough, we believe our commitment needs a real support by the rest of the football stakeholders: starting from all the true supporters, to all the stewards in the stands, from police and security agents, passing to media and as well through Lega Serie A and FIGC. Cagliari Calcio is asking you all a solid help to win a battle that involves everyone.