Tickets for U2's Croke Park concert in July are already exchanging hands for more than €900 each despite not officially going on sale until tomorrow.
A number of U2 tickets became available on official and black market websites last week after diehard fans with access to pre-sale tickets chose to sell them on for a profit.
Sources in the industry said a flurry of activity has seen fans splash out to guarantee their places at the gig.
Fans who subscribed to U2's official website were granted access to a pre-sale ticket portal last Wednesday. An annual subscription costs $50 (€47).
Tickets for the Lower Davin Stand and pitch areas of Croke Park have a face value of €76. There is an extra €3.30 charge for agent fees. Seats in other parts of the Cusack and Hogan stands range from €110 to €186. However, many of the tickets currently available on websites such as Seatwave and Viagogo are changing hands at much higher prices.
Seatwave is managed by Ticketmaster, the official ticket selling partner for the gig. It was advertising 650 tickets for sale last night. One pair of tickets for the standing section was being sold at €2,070 this weekend, including additional charges, 13 times above face value.
A spokesman for Ticketmaster said the Seatwave prices are not set by the company but by the person who is selling the tickets on.
"The thing about Seatwave is that it is a safe and secure market so tickets would be genuine. The ticket prices are set by the seller, which in this instance is not Ticketmaster, but that price may not necessarily be secured by the seller.
"Ticketmaster is just facilitating the sale."
Fine Gael TD Noel Rock, who has prepared a bill that would ban ticket touting, criticised the ticket retailer.
"We need this law to be enacted as soon as possible," he said. "Right now, the present situation suits touts, it suits Ticketmaster-owned Seatwave and as they make a commission from both buyer and seller, it suits Ticketmaster as it drives up early demand."