Football touts are enjoying their biggest ever end-of-season bonanza thanks to demand for four epic matches involving leading English clubs, reports the Daily Mail.
Some websites are already asking up to £4,500 for a ticket to next month's Champions League final in Moscow even though the line-up has yet to be decided.
UEFA officials say they are stunned to find internet touts are asking "astronomical" prices from supporters desperate to see the games.
A UEFA source said of the £4,500 tickets for the Champions League final: "This is greed beyond measure. But the problem is the final at the Luzhniki Stadium will be absolutely sold out and could be sold out twice over.
"That means these avaricious individuals can make many thousands of pounds from real fans who just want to see their heroes."
He warned that any of the three English clubs or Barcelona, on qualification, would have to pass on supporters' passport details to UEFA so they could be matched with tickets on entry to the stadium.