The Professional Footballers' Association called for a government inquiry into racism in football after Chelsea's 2-0 Premier League win over Tottenham Hotspur on Sunday was overshadowed by allegations of racism from sections of the crowd.
The allged vitriol flowed at the Tottenham Hotspur Stadium just after the Chelsea defender Antonio Rudiger was involved in a clash with Son Heung-min that led to the South Korean's dismissal.
Rudiger complained to the referee Anthony Taylor of hearing monkey noises from spectators.
The official halted play and an announcement was made over the public address system warning that racist behaviour was interfering with the game.
Two further public address announcements followed after play was resumed.
Following the game, Tottenham promised a thorough investigation into the incident.
"It's just such a shame that racism still exists in 2019. When will this nonsense stop?" Rudiger tweeted.
"I really hope that the offenders will be found and punished soon, and in such a modern football ground like the Tottenham Hotspur Stadium with dozens of TV and security cameras, it must be possible to find and subsequently punish them.
"If not, then there must have been witnesses in the stadium who saw and heard the incident."
The PFA said in a statement: "We are disgusted and dismayed that once again, a Premier League fixture has been tainted by abuse from the stands towards players.
"It has become clear that football players are on the receiving end of the blatant racism that is currently rife in the UK, but they are not alone.
"Racist abuse in football is not just an issue for black and ethnic minority players, it is an issue for everyone who loves the game. The PFA calls for a government inquiry into racism and the rise in hate crime within football."
Two weeks ago a man was identified and arrested for an alleged racist gesture caught on TV cameras during the match between Manchester City and Manchester United.
Aleksander Ceferin, the head of European football's governing body Uefa, said his organisation was attempting to crack down on the problem following a rash of incidents across the continent including a welter of insults hurled at England players during a Euro 2020 qualifier against Bulgaria in Sofia in October
Gary Neville, the former Manchester United and England defender, also accused top UK politicians of adding to the problem.
"We've just had a general election in this country with both main parties and the leaders of both main parties accused constantly of fuelling racism and accepting racism in their parties," said Neville on Sky Sports.
"If it's accepted in the highest office in the country, we're not talking at a micro-level, we're talking about it at the highest level in the country.
"Maybe we have to empower the players to walk off the pitch and stop the entertainment while it is happening," he added.
Apprentice outwits master
The antics in the stands took the sheen off the Willian double that gave Lampard an impressive triumph over his former Chelsea manager Mourinho.
The result maintained Chelsea in fourth place while Spurs dropped to seventh after the defeat.
"I hate racism in society, I hate racism in football," said Mourinho. "I'm disappointed that things like that can happen. The club is a very proud club in this kind of situation and internally we will try to deal with it."