Tickets for this Sunday's All-Ireland football semi-final are being advertised on a website linked to Ticketmaster at more than three times their stated face value, the Herald can reveal.
Four tickets for the crunch clash between Dublin and Mayo have gone on sale for €240.96 each on Seatwave.ie - a subsidiary of Ticketmaster - with the advertisement saying that the face value of the tickets is €65.
The four seats for the sold-out game are in the premium level of Croke Park's Hogan Stand.
The sale of the tickets is a breach of GAA rules surrounding premium level tickets, which are only supposed to be sold on by holders through the sporting organisation's ticket exchange system.
A GAA spokesman warned that the buyer of the tickets may not gain entry to Croke Park due to the strict rules surrounding the sale of premium tickets.
"We are resolutely opposed to the sale of any tickets above the price of face value," he added,
He said that the GAA monitors ticket sales and has the ability to cancel them if they are found to be sold at above the face value price.
Premium tickets are bought as part of packages ranging from €5,000 for three years to €12,500 for 10 years in the Hogan Stand and allow entry to multiple games.
The GAA spokesman said that he couldn't put a face value price on the tickets for that reason, but said that €240 is "above and beyond" what a GAA fan should pay for such tickets.
The seller of the four tickets that is using the Seatwave website has put the face value at €65 in the advertisement.
A spokesman for Ticketmaster said it is up to the seller to ensure that they comply with any rules set down by an event holder.
"The seller of tickets on the Seatwave marketplace needs to be aware of the terms and conditions under which they have purchased these tickets, in particular where resale is precluded," he said.
"Seatwave offers a 100pc money-back guarantee to the ticket purchaser as a layer of consumer protection, but will not protect sellers that attempt to sell tickets fraudulently," he added.
He said that Seatwave acts as a platform for individuals to list their unwanted tickets at a price that they choose.
"Ticket holders set the price and list their tickets for resale, not Ticketmaster. Nor does Ticketmaster divert tickets to this site," he added.