Cliftonville have told the fan who lit a flare in the recent Irish Cup defeat by Linfield to pay the resultant £500 fine out of their own pocket.
A statement from Cliftonville said that they are fully aware of the identity of the supporter involved.
The club has asked the supporter to pay the fine by midnight on 25 March.
The Cliftonville statement said the fan's failure to "settle the debt" would affect "other strands of day-to-day activity" within the club.
"With club officials and stewards subject to recent admonishment for an alleged lack of dedication to the fortunes of Ireland's oldest football club, we are only too pleased to take a step back in this particular instance and provide the guilty party with a one-week deadline to meet the financial burden which has been placed upon us," said the Cliftonville statement.
"If, come midnight on Friday, March 25, that individual has chosen not to settle the debt, the fee will instead be paid by the Football Club, who will be left with no choice but to redirect funds from various other strands of day-to-day activity, be it merchandising, youth development or indeed the playing budget."
Cliftonville confirmed on Friday night that the fine had been imposed by the Irish FA.
Linfield earned a 3-0 victory in the Irish Cup quarter-final which set up a semi-final against Lurgan Celtic.