It follows five days of sales to season ticket holders, with the club expecting to have sold 2,500-3,000 by the time the office shut on Monday.
Iron members could order their ticket online from 5pm on Monday, or via the club's ticket office or telephone hotline on Tuesday and Wednesday.
Tickets will go on sale to supporters who also order a ticket for the games against Bristol City or Ipswich Town on Thursday and Friday, with any remaining tickets going on general sale from next Monday.
Tickets will only be sold to people already on the club's database of supporters - people who have bought any ticket via the club.