Manchester City have made a formal complaint to UEFA over alleged racist abuse suffered by Yaya Toure against CSKA Moscow.
The Ivory Coast midfielder claimed that he was the subject of abusive chanting from some sections of the crowd during the 2-1 UEFA Champions League victory at the Arena Khimki on Wednesday, telling the media after the match that he had reported the taunts to referee Ovidiu Hategan.
He also used the opportunity to call on the European governing body to take action, adding: "It's unbelievable. I think UEFA needs to do something strong."
City have now followed that with an official complaint of their own, with a club statement on Thursday adding: "Manchester City FC can confirm that it has today issued a written formal complaint to UEFA regarding the events of last night's game against CSKA Moscow.
"It follows the complaint which was raised to the UEFA delegate immediately after the conclusion of the game.
"It is noted that UEFA have opened proceedings into the matter and we await the findings in due course."
The incident has once again brought the issue of racism in European football into sharp focus, with Toure's City team-mate Vincent Kompany leading the calls for a firm stance to be taken in order to rid the game of the problem.
He tweeted: "Racist chants again in Moscow. We've all said enough. @UEFAcom, @GovernmentRF, CSKA, all eyes are on you now. #StopRacism", while Everton manager Roberto Martinez added: "It is a real shame.
"I don't think we should be talking about these issues any more. It is important that FIFA and all the football authorities can do something about it.
"They must not let it go and accept it. It must not be another moment that can just be brushed aside."
UEFA confirmed to Perform on Thursday that they will wait for the referee's report before launching an investigation, but CSKA have been quick to refute allegations of racism.
They insist that their fans did not single out Toure for abuse.
A statement on the club's official website read: "We are surprised and disappointed by statements made by Manchester City player Yaya Toure alleging racially motivated insults from fans of CSKA.
"Having carefully studied the video of the game, we found no racist insults from fans of CSKA. In many occasions, especially during attacks on our goal, fans booed and whistled to put pressure on rival players, but regardless of their race.
"In particular, this happened with Alvaro Negredo and Edin Dzeko. Why the Ivorian midfielder took it as all being directed at him is not clear.
"It is an important fact that during the entire history of European competition our club has never observed, or been punished for, acts of racism from fans.
"In any case, we deplore this incident, although we believe accusations of racism are unfounded."
|Coach: L. Slutsky|
for V. Berezutski 6'
for S. Zuber 50'
|Belenenses 0 Pacos de Ferreira 1: Moreira seals rare away win|
|Juve angry at Roma draw - Allegri|
|Roma 1 Juventus 1: Keita keeps slim Scudetto hopes alive|
|Celta Vigo 1 Elche 1: Controversial late penalty gives visitors a point|
|Turkish Super Lig Review: Gala extend lead at the top|
|Paris Saint-Germain v Monaco: Jardim rejects de-facto final talk|
|Stuttgart, Freiburg named in doping claims|
|Dyche hails Ings determination ahead of Liverpool showdown|
|Newcastle United v Manchester United: Mata out to make more memories|
|England winger Johnson suspended after arrest on underage sex charge|
|Liverpool back in the black|
|Jedinak charged with violent conduct|
|BREAKING NEWS: Police make arrest on underage sex charge amid reports England international is held|
|Schone delighted to extend Ajax deal|
|Montolivo and De Jong suffer injuries|
|Bayern Munich v Eintracht Braunschweig: ´Self-critical´ holders in no mood to ease off, says Muller|
|Tottenham v Swansea City: Pochettino out to banish League Cup disappointment|
|QPR v Arsenal: Austin ready for survival fight|
|Sherwood: No hard feelings over missing out on West Brom job|
|Chelsea and Everton fined for fracas|
|Villarreal v Barcelona: Final in sight for visitors|
|Stoke City v Everton: Howard calls for back-to-basics approach|
|Pearson: I understand Pellegrini pressures|
|West Brom sweating on fitness of Berahino and Ideye|
|Manchester City v Leicester City: Pellegrini demands response|
|Feyenoord and Roma face UEFA charges|
|Liverpool v Burnley: Rodgers full of respect for visitors|
|Brown has red card overturned|
|Rodgers heaps praise on Allen|
|Koeman critical of Jedinak elbow|
|Bruce hits back at Hughes over Figueroa challenge|
|Koeman sets 61-point target for Southampton|
|Ibe set to miss a month with knee injury|
|Klopp looking to maintain momentum|
|Bent out for three to four weeks with hamstring injury|
|Schmidt ready for Kaiserslautern clash|
|West Ham v Chelsea: Mourinho turning attention back to the league|
|Barca must not be distracted by Clasico, says Busquets|
|Terry rules out England return|
|De Boer demands more despite PSV win|
|Bony: We have to win every game|
|Subotic rejects Serbia call-up|
|Benitez frustrated at refereeing decisions|
|Real Madrid must learn from Villarreal draw - Marcelo|
|QPR announce losses of £9.8m|
|Rutten to leave Feyenoord|
|First trophy for ´new´ Chelsea - Mourinho|
|Icardi the future of Inter, says Ausilio|
|Patience needed from ´brilliant´ United fans - Rooney|
|Allen hails ´next level´ Coutinho|
|Points over milestones for Cisse|
|Hecking ´furious´ with Wolfsburg defence|
|CONCACAF Champions League Preview: DC United face uphill task to reach semis|
|AFC Champions League Preview: Al Ain enhanced, Wanderers prepare for Evergrande reunion|
|Coupe de France Preview: PSG, Monaco to meet again|
|Crouch happy to silence doubters|
|Blanc questions rivals´ mental strength as PSG gain ground|
|Kane: Fortune favoured Chelsea|
|Ancelotti defends Isco substitution|
|Rooney: Di Maria will come good|
|Stubborn Villarreal impress Real´s Pepe|
|PSG could not ´kill off´ Monaco - Van der Wiel|
|Serie A Review: Napoli suffer defeat at Torino, Lazio lurking|
|Ligue 1 Review: Title chasers´ slip-ups go unpunished|
|La Liga Review: Real and Atletico suffer frustrating draws|
|Primeira Liga Review: Porto´s Tello dents Sporting´s title hopes|
|Monaco 0 PSG 0: Champions miss chance to go top|
|Real Madrid 1 Villarreal 1: Moreno leveller ensures stalemate|
|Simeone satisfied with Sevilla point|
|Henry: Chelsea can win a trophy treble this season|
|Mancini frustrated by ´hesitant´ Inter|
|Sevilla 0 Atletico Madrid 0: Simeone´s men in fiery draw|
|Pochettino upbeat despite League Cup defeat|
|Inter 0 Fiorentina 1: Montella´s men end San Siro wait|
|Bundesliga Review: Wolfsburg edge eight-goal thriller, Monchengladbach win|
|Mourinho revels in ´beautiful´ League Cup success|
|Eredivisie Review: PSV lose home record as Ajax close the gap|
|Terry thrilled by ´massive´ League Cup final win|
|Chelsea 2 Tottenham 0: Mourinho´s men seal League Cup success|
|Coquelin sustains broken nose|
|Wenger hails Giroud character after Everton goal|
|Everton not getting what they deserve - Martinez|
|Coutinho is coming of age at Anfield - Rodgers|
|Football League Preview: Wolves in the hunt for back-to-back promotions|
|Norwich City 2 Ipswich Town 0: Neil´s men go third with derby triumph|
|Southampton v Crystal Palace: Fonte focusing on big picture|
|Arsenal 2 Everton 0: Giroud strikes to silence doubters|
|Dynamo Dresden v Borussia Dortmund: Hummels eager to build on derby win|
|Rodgers tips hat to relentless Liverpool|
|City facing uphill challenge to retain title - Pellegrini|
|Celtic 4 Aberdeen 0: Champions dominate top-of-the-table clash|
|Lallana hails ´massive´ win as Liverpool´s top-four charge continues|
|Hull City v Sunderland: Cattermole allowing no excuses against ´bogey team´|
|Liverpool 2 Manchester City 1: Coutinho dents City´s title hopes|
|Sunderland to appeal Brown red card|
|Aston Villa v West Brom: Sherwood looking for confidence boost|
|Allegri not taking risks on Vidal and Pogba|
|Pardew defends Jedinak over Sakho elbow|
|Heldt apologises after Schalke´s derby humbling|
|Milan must give that bit extra - Bocchetti|
|Rooney: Brown red must be rescinded|
|Monk hails Swansea´s versatility|
|Melbourne Victory 2 Wellington Phoenix 3: Hosts miss chance to go top|
|Rodgers: Top-four finish would be bigger than last season´s effort|
|Batman and Robin ´a bit of fun´ - Reus|
|Rakitic feeling better after ending goal drought|
|Copa Libertadores Preview: Well-rested Cruzeiro ready for Universitario|
|Fournier fuming after Lyon loss|
|DFB Pokal Preview: Gladbach visit rusty Offenbach|
|Mourinho: Tottenham approached me|
|Primeira Liga Review: Birthday boys Benfica hit Estoril for six|