Croatian club HNK Rijeka have strenuously denied any of their players racially abused Manchester City's Seko Fofana in a friendly.
City's elite development squad coach Patrick Vieira took his team off the pitch when the 19-year-old French midfielder made the allegations after being sent off just before half-time.
Press Association Sport understands the move was supported by City officials and Vieira has received the backing of anti-discrimination network FARE.
However, Rijeka have issued a statement in which they dismiss the allegations.
"Rijeka clearly and unequivocally rejects any possibility that the players at the match against Manchester City participated in assaulting the rival players on racial, religious or ethnic grounds," said a statement on the club's website.
"We want to point out the fact that we mentioned at the game we had six players from the Nigeria squad, players who live and train together with our other players, who learned the Croatian language and who have never experienced any discomfort by team-mates - as they themselves can attest.
"We also want to point out that Rijeka, in co-operation with FARE, supports a campaign against racism and strongly condemns any incident of its kind.
"Because of this, we are surprised by the unpleasantly harsh and baseless accusations of which we are accused and that we completely reject."
Ranko Buketa, who was in charge of Rijeka's team on Tuesday, accused City of trying to divert attention away from Fofana's actions which led to his red card.
"It looks like a move which is trying to hide a very ugly foul by the Manchester City player that resulted in exclusion, followed by a hasty and illogical decision of the coaching staff to withdraw the team from the field," he told the club website.
"Such an abrupt decision surprised us as it was made by responsible people at a respectable club like Manchester City."
Piara Powar, executive director at FARE, felt Vieira, a Senegalese-born former France international, did the right thing.
"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 told Press Association Sport.
"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.
"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 European countries, would be raising the matter with FIFA and he urged City to do the same.
"If it was bad enough to take the team off I would hope they would make a complaint," he added.
It is not the first time City's players have been involved in such incidents.
CSKA Moscow were ordered by UEFA to close part of their stadium after midfielder Yaya Toure was racially abused during a Champions League match in October.
Porto were fined £16,700 in April 2012 after their supporters directed racist chants at Toure and striker Mario Balotelli, who has since left the club, during a Europa League tie.
Youth team striker Devante Cole, son of former Manchester United and Newcastle forward Andy, was racially abused by players and supporters during a UEFA Youth League match against Atletico Madrid in February.
Vieira's decision to lead his side off the pitch is not the first time players have taken direct action in the face of abuse.
Midfielders Kevin Constant and Kevin Prince Boateng both walked off with their team-mates in separate incidents while playing for AC Milan and Watford Under-19s took similar action during a match in Italy in December.
There has been no response so far from either FIFA or the Croatian Football Association and City are still considering the next course of action.