The Spireites head to Bramall Lane on Saturday for the second time in the space of just three months.
The pair’s last encounter was a 1-1 draw on Sunday, May 3 - the final game of the 2014/15 season.
An Ian Evatt header shortly after half-time gave Chesterfield a share of the spoils, as the Spireites finished the regular season off with a battling draw.
Marc McNulty had given the Blades a lead just after the half-hour mark with a thunderous effort but few of the 26,078 at the game would argue Chesterfield didn’t deserve at least a point.
The draw, coupled with MK Dons claiming automatic promotion and Preston losing at Colchester, meant that a Thursday meeting between the Spireites and Simon Grayson’s Lilywhites at the Proact before a second leg at Deepdale on the Sunday.
Chesterfield, of course, went on to lose that eventual semi-final to the overall winners, whilst United were edged out by Swindon Town 7-6 on aggregate in a thrilling second leg encounter.
Since that clash much has changed at both clubs.
For a start, both are under new management with Paul Cook’s exit to Portsmouth leading to Dean Saunders’ appointment.
As for United, they dispensed with Nigel Clough’s services and replaced him with former Southampton and Scunthorpe chief Nigel Adkins.
Both appointments looked shrewd at the time and Saturday’s clash will be an intriguing early season head-to-head.