Aberdeen have sold less than half of their League Cup semi-final tickets despite complaining about their initial allocation for the tie against Rangers.
The Pittodrie club eventually received 20,300 tickets for the game at Hampden on Sunday, 28 October after denouncing their original share of 16,800.
However, Aberdeen have sold just over 9,000 to date, and admit sales "have fallen short of the demand expected".
The SPFL has taken back some sections of the club's allocation.
However, 5,500 tickets are still available, and the club confirmed they will have "access to a further allocation if we demonstrate additional demand in the next few days".
A statement added: "The focus now quickly turns to fulfilling the remainder of our allocation to ensure that the team walk out to a wall of noise from Dons supporters in attendance."
Manager Derek McInnes suggested that the school holidays may have an effect but reiterated that he wants "as many supporters there as possible because it helps the team".
'We've got more options now'
McInnes has been heartened by an easing of the club's injury list during the international break, with strikers James Wilson, Stevie May and Scott Wright, and winger Niall McGinn, all returning to training.
All four - plus teenager Connor McLennan, who has recovered from a shoulder knock - are available for Saturday's trip to Premiership leaders Hearts.
Midfielder Greg Tansey, who has yet to play this season after a persistent groin problem which required three operations while on loan at Ross County last term, has also returned to training.
"We have got a few more attacking options now," McInnes said. "All of a sudden we are getting international players back in and the squad has swelled and looks strong.
"This season has been the most challenging injury-wise in my time here, but hopefully that is the worst of it over now and we can push on."
McInnes will be without centre-back Scott McKenna, serving the second of a two-match ban, for the trip to Tynecastle.