Chesterfield took advantage of an early second-half red card for Grimsby goalkeeper Christy Pym to win a close game 1-0 at Blundell Park.
Pym was shown a straight red for a last-man challenge on Lee Bonis, and Harvey Rodgers’ own goal was enough to secure victory for the Spireites.
Chesterfield keeper Zach Hemming was first to be tested, doing well to stop Jaze Kabia’s first-time effort from just outside the six-yard box.
Ronan Darcy dragged a shot past a post for the visitors, while Kabia headed wide from a Reece Staunton cross as the first half ended scoreless.
The hosts forced saves from Hemming early in the second as Jamie Walker and Charles Vernam fired efforts on target.
Pym saw red in the 53rd minute as Bonis beat him to a loose ball just outside his penalty area.
The visitors made their numerical advantage count in the 72nd minute as Dilan Markanday’s low cross was turned home by the unfortunate Rodgers.
