Tickets to see Manchester City entertain Manchester United at the Etihad Stadium on Monday have been selling for £1,300 online.
The clash is likely to decide the destination of the Premier League title, with just three points separating the two sides with three games to play.
And according to The Sun, the online sales have led to police fears of rival fans sitting next to each other.
A Greater Manchester Police spokesman said: ‘We’d warn fans that if they buy tickets online they could be fakes and if home fans end up in the away end or vice versa they’ll be identified early on and ejected.’
A Man City spokesman said: ‘We’d always advise fans to only purchase match tickets through the official club channels.’
The cost of the online tickets equates to £14 per minute of football.
