Chesterfield are still clinging to a second division life line after Derek Niven scored his first goal in senior football to see off a well below par Blackpool team.
A game which contained few moments of any quality was settled by a well-worked goal in the 20th minute and Blackpool rarely troubled Chesterfield keeper Carl Muggleton after that.
The visitors did not manage one shot on target in the entire game and only a penalty save by stand-in keeper Steve Elliott, after Philip Barnes had been sent off, denied Chesterfield a second goal.
This was a match the home side had to win and they always looked the more committed and urgent of the teams although there was one moment of good fortune for them in the 19th minute.
A defensive mix up allowed teenage striker Matt Blinkhorn the chance to lob Muggleton but the ball landed on the roof of the net.
It was not an easy chance but a more experienced striker might have put it away and within 60 seconds, Chesterfield had gone in front.
Glynn Hurst broke away down the Blackpool right and after turning past Elliott, squared the ball for the on-rushing Niven to place a right foot shot past Barnes from 12 yards.
Chesterfield could have scored again when Hurst lobbed Barnes but Mike Flynn cleared and then blocked Chris Brandon's follow up.
The second half became increasingly edgy for the home side with David Reeves hitting the side netting in the 57th minute but Blackpool rarely posed a threat.
Substitute Andrew Mangan put a left foot shot over the bar from 12 yards but there was little end product from the visitors although Chesterfield created few chances themselves.
They should have scored again in the final minutes when the excellent Niven put substitute Marvin Robinson through and the striker was brought down as he side-stepped Barnes.
Referee Paul Armstrong had no option but to show the red card to the keeper but his stand in Elliott dived to his right to push away Hurst's weakly struck spot-kick.