A 53-year-old Irish man remains in a critical condition following an assault before Liverpool's Champions League semi-final against Roma at Anfield last night.
Sean Cox from Co Meath is being treated at Walton Neurological Centre.
Merseyside Police said he had been attacked near the football ground with a belt and sustained a head injury.
It is understood he travelled to the game with his brother.
Two men from Rome, aged 25 and 26, were later arrested on suspicion of attempted murder.
Mr Cox is a member of St Peter’s GAA club in Dunboyne.
The club said in a statement: "The Club is aware of an incident involving our Club colleague, Sean Cox, at the Champions League game in Anfield last night.
"Sean is a long serving and popular member of St Peter's GAA Club in Dunboyne. At this point we hope that Sean is receiving all of the medical care he requires and that he makes a full and speedy recovery.
"Our thoughts and prayers are with Sean and his family, and we hope that they get the privacy and space they need. We will not be making any further statement at this time."
Liverpool FC issued a statement saying the club was "shocked and appalled".
"Our thoughts, in the first instance, are with the victim and his family at this very traumatic time. We will be offering them our full support."
Liverpool captain Jordan Henderson posted on Instagram his "thoughts and prayers" were with Mr Cox.
UEFA condemned the attack: "UEFA is deeply shocked by the vile attack that occurred ahead of the Liverpool FC v AS Roma match and our thoughts are with the victim and his family.
"The perpetrators of this ignominious attack have no place in and around football and we trust they will be dealt with utmost severity by the authorities.
"UEFA is waiting to receive full reports before deciding on potential disciplinary charges."
Roma also condemned the "abhorrent behaviour" of a small number of their supporters.