The Spireites secured a play-off place in the National League as goals from Liam Mandeville and Nathan Tyson were enough for a 2-1 win over FC Halifax Town at The Shay.
Manager James Rowe kept the same side that secured the crucial win over Dagenham & Redbridge last weekend.
The home side started the brighter of the two teams with the Chesterfield defence doing well to keep the ball away from the six-yard box.
However, the Blues took the lead in the 15th minute. George Carline’s long throw was flicked onto the back post where Mandeville nodded home from close range.
After a quiet period following the opening goal, Halifax drew themselves level. Darren Stephenson benefited from an error by Manny Oyeleke before firing past James Montgomery at the near post.
The Spireites were dealt a huge blow with ten minutes to go until half time as Danny Rowe was forced off with an injury; Tyson replaced him.
Carline was presented with a chance to put the visitors back in the lead but the wing-back slipped as he went to take the shot.
A change was made at half time as Alex Whittle came on for Joel Taylor in a straight swap.
Halifax came inches away from taking the lead just a couple of minutes into the second half. Jake Hyde’s header was excellently saved by Montgomery before Martin Woods had his effort cleared off the line by Oyeleke.
Both sides were looking for the all-important goal and Laurence Maguire came close as his header was well saved by Sam Johnson.
Following that chance, the game slowed down as both sides tried to chase a play-off spot.
With ten minutes to go, the Spireites scored a massive goal. The ball was slipped through to Mandeville and the midfielder provided a low ball for Tyson to prod home from just a few yards out.
The Spireites defended resiliently for the last ten minutes and secured the win that secured sixth place and a spot in the play-offs. Chesterfield will play Notts County at Meadow Lane next Saturday (4pm).
Chesterfield: Montgomery, Carline, Evans, Gunning (C), Maguire, Taylor (Whittle 46), Weston, Oyeleke, Clarke, Mandeville (McCourt 83), Rowe (Tyson 36).
Unused Substitutes: Whelan, Yussuf.