Chesterfield kept their sixth successive clean sheet as a narrow victory over Blackpool lifted them into the play off positions.
David Reeves scored the only goal of a tight game when he volleyed home his first of the season just after the break.
But Blackpool missed a host of chances to haul themselves level and found themselves leapfrogged by the Spireites in the table.
Blackpool started the brighter and could have gone ahead after just 24 seconds when John Hills put Scott Taylor through on goal.
But the former Tranmere man hesitated and the chance was lost as the ball ran out of play.
The Tangerines continued to dominate and Hills was again involved after 23 minutes when his long-range shot flashed just wide.
The home side didn't have an effort on target until the half-hour mark when manager's son, Andy Rushbury shot well over after Jamie Burt found him unmarked on the penalty spot.
Then ten minutes later Reeves should have put his side ahead but shot straight at Phil Barnes when Blackpool failed to clear a cross by Rushbury.
Reeves made amends two minutes into the second half when he put Chesterfield ahead to open his account for the season.
The veteran striker fired past Barnes from just eight yards when Stuart Howson nodded Rushbury's free-kick back into the box after it had been partially cleared.
After Reeves' strike it was one-way traffic as the visitors went in search of an equaliser.
First Richie Wellens, then Taylor had shots well saved by Chesterfield keeper Carl Muggleton in the space of a minute.
Substitute Richard Walker then had a good opportunity but his close-range effort was superbly blocked by Howson.
Muggleton then held a late shot by Walker to ensure his side climbed to fifth in Division Two