Rangers player Glen Kamara has said he was the victim of "vile racist abuse" when his team played Slavia Prague on Thursday.
In a statement issued through his lawyer Aamer Anwer, Kamara accused Slavia defender Ondrej Kudela of directing a racial slur at him.
The statement read: "If UEFA genuinely wants to ‘show racism the red card’, then it’s time to stop the tokenism and take a zero-tolerance approach.
"As a player I do not expect myself, nor any other to have to tolerate racial hatred on or off the pitch in 2021.
"The vile racist abuse by Ondrej Kedel (sic) took place on the international stage, and any failure to act by UEFA will be viewed as a green light for racism."
The statement comes as it emerged Slavia Prague had asked police to investigate claims a Rangers player allegedly carried out an assault in the Ibrox tunnel.
The side claim Gers boss Steven Gerrard is a key witness.
The fresh allegations come with Light Blues chiefs having earlier hit back at what they claim are deflection tactics aimed at masking the racism storm which erupted following Thursday’s Europa League clash.
Midfielder Glen Kamara had to be held back by team-mates as he reacted with fury when Czech defender Ondrej Kudela wandered alongside him late in the game, cupping his hand before whispering an alleged racist remark into the midfielder’s ear – something Kudela denies.
Rangers have stood by Glen Kamara's account of the alleged racial abuse by a Slavia Prague player, despite the Czech team insisting it was the Scottish club causing the problem.
Slavia have hit back, rejecting the racism claims while accusing Kamara of being the guilty party responsible for an assault on Kudela in the tunnel after the final whistle.
However, police bosses admit they know nothing about Slavia’s claims that Kamara swung a punch at their player.
UEFA has said it is ready to probe the post-match incident but Gerrard has already warned they must not allow the racism claims to be "brushed under the carpet".
Rangers managing director Stewart Robertson has also turned up the heat on European football’s governing body as he insisted “enough is enough".
“Racism is unacceptable in any form and in any setting,” he said in a statement. “The racist abuse suffered by Glen Kamara will not be tolerated by Rangers. As a club, we stand resolutely behind Glen as we support him and his teammates.
“Several of our players have subsequently received racist, threatening and sickening abuse online. This is abhorrent and once again highlights the responsibility social media outlets have in eradicating abuse from faceless cowards.
“We refuse to acknowledge any attempt to defend, deflect or deny the abuse Glen Kamara experienced last night.
He added: “UEFA will be well aware the football world is watching. We expect a robust and unequivocal response in relation to this incident. It cannot be merely ‘swept under the carpet’- we are not prepared for Glen Kamara to be yet another statistic. Enough is enough.”
UEFA confirmed it is investigating allegations of ugly scenes after the match – which saw Rangers lose 2-0 and have both Kemar Roode and Leon Balogun sent off – had ended.
UEFA has already announced it will be investigating the game – but Slavia are also demanding that police officers probe events.
In a statement, the Czechs – who now will face Arsenal in the Europa League last eight – said: “Slavia Prague filed a criminal complaint with the Scottish Police through the Embassy of the Czech Republic in Great Britain for physically assaulting player Ondrej Kudela.
"The submission contains the names of witnesses who, in addition to representatives of Slavia Prague, were also representatives of the UEFA delegation and Rangers coach Steven Gerrard."
Slavia countered Rangers’ claims, insisting Kudela was the victim of an attack from Kamara.
They also took aim at the rest of Gerrard’s team, accusing the Ibrox club of “unprecedented malicious play”.
Ondrej Kolar was left with a fractured skull and huge three-inch gash on his forehead after Roofe planted his studs into the Slavia keeper’s face with a brutal high challenge, while Balogun also walked after collecting two bookings.
In a statement, Prague bosses said: “The club denies the allegations of racism of one of the team captains Ondrej Kudela.
“Slavia resolutely denies the disgusting accusation of one of the team captains Ondrej Kudela of racist behaviour
Kudela said after a brutal foul by Rangers he went up to Kamara and said: "You f****** guy’. It was said in emotions, but I absolutely deny there was anything racist in those words."
Slavia accused Rangers of playing dirty with many fouls resulting in player injury, saying they had never seen play like it any modern football.
One tackle left Goalkeeper Ondrej Kolar needing 10 stitches on his head.
They said: “Ondrej Kudela was assaulted by player Kamara and hit with fists in the head with manager Steven Gerrard witnessing the incident.
“Even the UEFA representatives who were also present on the site of the incident were shocked by this behaviour. The team is now safe accompanied by the Scottish police.”
But a Police Scotland spokesperson said: “No reports of criminality have been made by either club in connection with last night’s match.
“Police Scotland has contacted club officials and assured them that should any allegation be received it will be investigated thoroughly.”