Wrexham star James McClean has confirmed he threw a punch at a Cardiff fan before last week's all-Wales encounter in the Carabao Cup.
The teams met for the first time in 21 years last Tuesday, when the League One side beat Wrexham 2-1 to earn a quarterfinal against Chelsea.
Reports subsequently emerged that McClean swung at a Cardiff fan before the SToK Cae Ras clash, with the Republic of Ireland international confirming to UK radio station talkSPORT that an incident took place.
The 36-year-old alleges he was confronted in the players' car park by four Cardiff fans who "started running their mouths off", with the winger saying he reacted after their second jibe.
"Words were said," McClean told talkSPORT. "One of them, a tall chap with glasses, made a hostile move towards me ... I'm in my workplace and I feel I should never feel threatened in that workplace.
"So instead, I wasn't waiting for him to make the first swing, so I did. Four men, one of me.
"People need to understand just because we play football doesn't mean people can try and take liberties without their actions having consequences.
"That was it. Nothing further happened. And the situation was dealt with."
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North Wales Police have been contacted by the PA news agency.
Wrexham said in a statement to PA: "Wrexham AFC are aware of an incident involving a first-team player and a visiting supporter ahead of our match against Cardiff City, which has been reported to the relevant authorities.
"We will be making no further comment on the matter at this stage."
Wrexham face Portsmouth at Fratton Park in the Championship on Wednesday evening.