Jones returned to the side just a fortnight after undergoing a groin operation. And, as the game looked to be heading for a goalless draw, he swung his little used right foot at the ball 25 yards from goal and it flew into the net off the underside of the bar.
In addition to being Jones' first goal it was also the first shot on target Yeovil had in what was largely a disappointing afternoon.
Yeovil's joy was matched by despair from the Spireites who needed points in their battle for survival. After five defeats they drew with Doncaster in midweek and looked destined for another draw until Jones struck.
Chesterfield had the better of the first half and might have taken the lead in the fifth minute when a defensive mix up let in Paul Shaw. The alert Steve Mildenhall raced from his goal to block with his legs and Paul Hall, who followed up, fired over the bar.
In the second half Yeovil had much the better of things. Their danger came from Arron Davies, who had been released from the Welsh squad by John Toshack to play in this match.
He was right out of luck in the 78th minute when he appeared to be clean through but was brought down by Reuben Hazell, who was lucky to escape with a yellow card.