It was supposed to be a shining emblem of West Ham’s enlightened future – but now it has been marred again by a reminder of a dark past.
Trouble flared within the London Stadium again at the first London derby since it became the home of the Irons.
Although it was an isolated incident on Wednesday, towards the back end of the game, it still provided scenes that challenge the branding of West Ham Utd as a family-friendly club – and were frightening for those caught up in the violence.
One Chelsea fan said he and his eight-year-old daughter were pelted with coins.
The unnamed man told the BBC: "She's been going since she's two. She's never experienced violence like this before or the aggression that we've had to suffer.
"We've never been hit by coins before - to be hit by seven of them in one evening, that's why we've kept them."
Yet again, segregation was the issue and yet again the speed and efficiency of the stewarding was brought into question as Chelsea and West Ham supporters were able to get into spitting distance, seats becoming weapons.
This time, for the first time, police in riot gear were in the stadium and made an effective intervention – but police in riot gear is not the image the east Londoners want to send round the world.
Seven arrests were made as bottles and coins were thrown as hundreds of supporters clashed, the 2-1 victory by West Ham in the EFL Cup suddenly a forgotten cause of cheer.
“We are totally against it as a club,” said Slaven Bilic and any fans identified will be banned for life. They will join 23 others already banned from the stadium since it opened. The club said it “unreservedly condemned” fans’ behaviour.
One Chelsea supporter told BBC Radio : “It was like being back in the 1970s. The amount of coins that were thrown, seats that were thrown, it was an absolute nightmare.”
The Metropolitan Police, who made seven arrests for alleged public order offences, described Wednesday’s incidents as “unacceptable”.
Images on social media before the game appeared to show a song sheet being distributed with homophobic lyrics aimed at Chelsea defender John Terry and striker Diego Costa and these, too, would be investigated.
Police commander BJ Harrington said: “There were a minority of people who attended the match that were clearly intent on being involved in confrontation and violence.
“Despite extensive work with both clubs and a large and robust policing operation, there were unacceptable incidents inside and outside the stadium, before, during and after the game.”