UEFA said on Friday it was investigating incidents in Rangers' Europa League clash with Slavia Prague after the Scottish club's midfielder Glen Kamara complained of being racially abused by a visiting player in Thursday's 2-0 defeat in Glasgow.
Rangers were knocked out of the competition following a 3-1 aggregate loss in their last-16 second leg after having two players sent off in a heated encounter which saw a melee on the pitch and clashes in the tunnel after the game.
"An Ethics and Disciplinary Inspector will conduct an investigation regarding the incidents that occurred," European football's governing body UEFA said in a statement.
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Kudela said in a Slavia statement that he swore at a Rangers player after being fouled, but denied using racist language.
Slavia also alleged that Kudela was assaulted by Kamara after the game and have officially complained to Scottish police.
Rangers boss Steven Gerrard called on UEFA to take action.
"My player tells me he was racially abused," Gerrard said.
"I feel angry... I know Glen and I trust him 100% and it is extremely disappointing.
"If I wanted to say something to you on a football pitch, why do I need to cover my mouth and go to the ear?
It is over to UEFA now this situation and I just hope it doesn't get brushed under the carpet.
Kamara issued a statement on Friday through his solicitor.
"There is no place for racism or any form of bigotry in football," the statement read. "Since (the) summer many of us have taken the knee in solidarity with those who have lost their lives to racial violence.
"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."
SLAVIA DENY ACCUSATIONS OF RACISM
Czech club Slavia defended Kudela against the racism allegations, saying in their statement: "Slavia resolutely denies the disgusting accusation... (against) Ondrej Kudela of racist behaviour.
"Slavia players faced unprecedentedly malicious play from their opponents... After the end of the game, the team was not allowed to enter the dressing room.
"Ondrej Kudela was assaulted by Kamara and hit with fists in the head when Rangers manager Steven Gerrard witnessed the incident."
Slavia have since lodged an official complaint with the Scottish police, via the Czech Embassy in London, alleging a "physical assault" on Kudela.
"Physical assault on Ondrej Kudela was prepared and (a) deliberate act," the Slavia statement said. "The assault was brutal and carried out with the full force with the intention to hurt and cause physical harm to our player.
"In the text, the names of people who witnessed the incident are stated, including UEFA representatives and Rangers FC manager Mr Steven Gerrard."
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.
UEFA said earlier on Friday it was aware of an incident in the tunnel involving players from both sides and was awaiting detailed information from the match officials.
Rangers' Kemar Roofe was also subjected to racial abuse on social media after being shown a red card for a high-boot challenge on Slavia's Ondrej Kolar, which the Czech club said resulted in the goalkeeper needing 10 stitches to his head.
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