The club’s head of the elite development squad made the decision after 19-year-old French midfielder Seko Fofana was allegedly racially abused by an opponent a minute before half-time in the match against HNK Rijeka in Novigrad, west Croatia.
Vieira, a Senegalese-born former France international, has received the full backing of Piara Powar, executive director at anti-discrimination network Fare.
“We are not, in the short term, able to stop this sort of incident happening, but to have someone like Patrick Vieira, with his status, do this makes the message very clear,” Powar said.
“The message it sends out is categorical. It is just the sort of thing which will create change. We have got to challenge any situation in that regard.
“Where it involves young players and it happens in a friendly match, which is of little consequence, you have to look at damage it might do to them and safeguard them against that.
“We hope it will educate their [Croatia’s] younger players in the future, particularly when they play more teams with more diversity but I am sorry to say I think it will continue.
“Rijeka are professing puzzlement as to why the team were taken off but I don’t think Patrick would have done that without good cause.”
Powar said his organisation, which is active in more than 40 countries, would raise the matter with Fifa and he urged City to do the same. “Under-21 matches are governed by Fifa and I hope Manchester City are going to make a complaint and pursue it,” he said. “If it was bad enough to take the team off I would hope they would make a complaint.
“We will be alerting Fifa to this. Fifa’s reaction to incidents reported in the World Cup this summer was to turn a blind eye to it.”
City reacted quickly to Tuesday’s alleged incident, which according to the club’s Twitter feed followed moments after Fofana had been sent off for an off-the-ball clash, issuing a statement to clarify Vieira’s actions.
“Manchester City’s EDS U21 game with HNK Rijeka has been cancelled due to an alleged incident of racial abuse toward the club’s young midfielder, Seko Fofana by a member of the opposing team,” said a statement on mcfc.co.uk. “Club representatives in Croatia and in Manchester are liaising with officials, the match organisers and the Croatian Football Association to pursue this matter further.”
A statement on HNK Rijeka’s website read: “Manchester City coach Patrick Vieira entered the field, something was discussed with the referee, and then to the amazement of a well-filled stadium he took his team off the pitch. What are the reasons? They are known only to him.”