After consultation between the two clubs, Chesterfield's ticket allocation at Oldham Athletic on Saturday has been increased to a total of 2,000 for Spireites fans.
Chesterfield supporters are asked to note that all ticketsmust be bought in advance and there will be no tickets available at Oldham on matchday.
The ticket office had initially received 1,000 tickets for the Boundary park match, the majority of which have already been sold - but 1,000 more have been received and are on sale now.
All tickets sold for the match, including those already sold, will be unreserved in the away stand on Saturday.
True Blue Travel tickets are also still available at the club and can be ordered online, over the phone or in person at the Club Superstore.