Arsenal have threatened to ban supporters found to have sold their tickets to Bayern Munich fans ahead of their Champions League quarter-final first leg tie tomorrow.
Bayern will travel without an away contingent after their fans were banned by UEFA for throwing fireworks onto the pitch during matches at Copenhagen and Lazio.
However, figures at Arsenal are said to be concerned that Bayern supporters may still try to buy tickets in the home end and as such have taken steps to prevent this.
To avoid potential incidents, Arsenal have not sold tickets to any new members that registered for the ticket ballot after March 11, in advance of the last-eight draw.
Season ticket holders are only able to offload their tickets via the club's official ticket transfer service to supporters whose accounts were created before the same date.
Those found to have broken these rules will be hit with indefinite bans.
'There is additional risk associated with this game, because Bayern Munich are not permitted an away allocation,' Arsenal told supporters.
'Any season-ticket holder or Arsenal member's seat found to be in possession of an away fan will be suspended indefinitely.'
Bayern, who were also hit with a suspended one-match ban and £30,000 fine for a pyrotechnics incident in Copenhagen, have urged their supporters not to travel.
The club have been given an allocation of just 200 tickets for friends and family, while around 20 senior club officials will be seated in the directors' box.
Arsenal are seemingly determined to avoid a repeat of unsavoury scenes in 2017, when thousands of Cologne supporters bought tickets for a Europa League game.
However, they did so through club members and other ticketing websites, sparking several disturbances around the ground and forcing the police to deploy dogs.
Kick-off was delayed by an hour after violent scuffles broke out, with groups of Cologne fans also clashing with stewards, the police and home supporters.
Arsenal will arguably be strong favourites to progress to the semi-finals at the expense of Bayern, especially with Mikel Arteta's side topping the Premier League.
Bayern, meanwhile, are second in the Bundesliga and will fail to retain their title.