Gary Roberts made one goal and scored the other as he masterminded a deserved 2-1 victory at Port Vale for Chesterfield with a man-of-the-match display.
The visitors dominated most of the early play and took the lead in the ninth minute when Eoin Doyle kneed in the rebound from four yards after Roberts' shot had came back off a post.
Tom Pope struck the outside of a post as Vale attempted to fight their way back and the home side levelled against the run of play five minutes before the break.
Mark Marshall burst into the Chesterfield box from the right flank and smashed an angled drive high inside visiting goalkeeper Tommy Lee's left-hand post from 14 yards.
Vale should have gone ahead just two minutes later when Pope's cushioned header dropped perfectly for Chris Lines, who miscued with the goal at his mercy.
But Chesterfield were back in front just 16 seconds into the second period. Roberts mesmerised Ryan McGivern before placing an angled left-footed shot which clipped the inside of the far post on its way in.
Colin Daniel forced a fine save from Lee before former Vale midfielder Sam Morsy retaliated when he rattled the crossbar from 30 yards.
Chesterfield were reduced to 10 men for the final seven minutes after Ian Evatt was sent off for a second bookable offence.