Dale were beaten by two penalties as Chesterfield secured a 2-0 win in Dale's last ever trip to Saltergate.
A goalless first half was dominated by Dale, with Jason Kennedy having Dale's best chance, as he was denied from a few yards out by a goal-line block by Phil Picken.
The second half was very even up until the 69th minute when Nathan Stanton was deemed to have handled inside the penalty area. Barry Conlon scored from the spot, and doubled his tally from the spot moments later after Rory McArdle had fouled Wade Small.
Dale strived for a way back into the game but it wasn't to be as Keith Hill's side came away from Chesterfield pointless.
Keith Hill stuck with the same eleven that saw off Grimsby 4-1 last Saturday, as his side looked for their fourth win in a row. Frank Fielding was in goal, with Scott Wiseman, Nathan Stanton, Rory McArdle and Tom Kennedy making up the back four. Ciaran Toner, Gary Jones and Jason Kennedy were in midfield, with Joe Thompson playing in the free role behind Chris O'Grady and Chris Dagnall. Former Dale players Tommy Lee and Adam Rundle were in the Chesterfield line-up.
It was Dale who had the better of the opening exchanges, with Chris O'Grady popping up in and around the box on several occasions as Dale looked for the opening goal. The three man midfield Dale had set up was causing problems for Chesterfield as they went long looking for target man Barry Conlon.
With 25 minutes gone in the first half both sets of supporters inside Saltergate were still waiting for the first real chance of the game. Both sides had been in attacking positions, more so Dale, but neither had carved out a real opening. Chris O'Grady forced Tommy Lee into a low save with a tame shot from just inside the area, but the former Dale loanee made a comfortable stop.
Chris Dagnall was keeping the Spireites stopper warm as he tried a left footer from outside the area, but Lee made another easy save. The home 'keeper then had a heart in the mouth moment when he let the ball free of grasp after landing heavily, but under the attentions of Dagnall he was able to smother the ball before any damage was caused.
With 32 minutes played the first chance finally came, and it fell to Dale's Jason Kennedy. Chris O'Grady and Chris Dagnall played a superb one-two in behind the home defence, with Dagnall squaring for Joe Thompson. After Thompson was forced slightly away from goal he backheeled cleverly to Kennedy, but the midfielder placed his shot in the one place where he didn't want to, as it struck the Spireites' Phil Picken on the line before going out for a goal-kick. Jason Kennedy will have to wait a little while longer for his first goal in Dale colours.
Keith Hill's side were really cranking up the pressure as the game approached half-time. Neat interplay in the final third of the pitch had Chesterfield worried but the ball wouldn't fall in the right place for Dale as they began to grow in confidence.
The league leaders still had to be aware at the back though as the home side proved themselves capable of breaking on occasion. Striker Wade Small had a good effort from outside the area which just flew wide of Frank Fielding's goal - although the Dale stopper was comfortable.
Two minutes of added time were shown by fourth official Plowright, but neither side could produce in the remaining seconds and the sides went into the break goalless.
Dale were hoping they could dominate the second half as they did the first, but it was John Sheridan's men who started the brighter of the two teams, with former Dale man Adam Rundle having a scuffed shot which caused problems for Frank Fielding before rolling out for a corner.
Chris O'Grady was still looking like Dale's biggest threat going forward, and it was he who had the first shot of the half for Dale, but he dragged his right foot effort just wide of Tommy Lee's goal.
With 57 minutes played Chris Dagnall forced Tommy Lee into a save with his legs after a quick Dale break. Dagnall played the ball ahead of him to Jason Kennedy who in turn played a majestic backheel pass to Dagnall, but the striker's shot was turned away by Lee with his legs.
The game was becoming a lot more open as both sides pushed for that opening goal. Adam Rundle, who was finding pockets between Dale's midfield was put through by Mark Allott, but Frank Fielding was equal to Rundle's rising shot as he palmed it away for a corner.
In the 65th minute Kallum Higginbotham was brought on for Jason Kennedy as Dale reverted to a 4-4-2 formation. Higginbotham's first touch brought about a corner for Dale, but nothing came from it.
Then came the most controversial moment of the game as referee Quinn awarded the home side a penalty. Ishmel Demontagnac crossed the ball which hit the sliding Nathan Stanton in the arm. There was no doubt it hit Stanton in the arm, but the Dale centre-back was a matter of yards away and had no chance to get out of the way. Barry Conlon took the spot kick which Frank Fielding got a leg to, but the ball luckily rolled over the line to give Chesterfield the lead.
It was a setback for Dale but they would need a good response, and they almost got one but for Tommy Lee. Kallum Higginbotham drove the ball in low which found the feet of Chris O'Grady, but former Dale stopper Lee made a fine save down low to stop the shot and turn it behind for a corner.
With 72 minutes gone Craig Dawson, and his face mask, came on for Nathan Stanton, whilst 4 minutes later Joe Thompson came off for Temitope Obadeyi who went over to the left wing.
As the clock wound down Dale just couldn't find a way to break down Chesterfield, with the home side looking dangerous for a second goal. With 81 minutes on the clock they were awarded another penalty when a breaking Wade Small was brought down by Rory McArdle who was awarded a yellow card. If there were doubts about the first penalty, there were none about the second. Barry Conlon stepped up again and beat the hand of Frank Fielding for his and his side's second goal.
With not long left on the clock all looked lost for Dale as they failed to find the feet of their team-mates on separate occasions in the final third, although you can never write this Dale side off.
But it seemed that second goal provided the killer blow for Dale and four additional minutes didn't make any difference, despite a superb reaction save by Tommy Lee to deny Craig Dawson his 12th goal of the season.
It's a minor setback for Dale in their promotion push, but Keith Hill's side are still sitting pretty on top of the League Two table.
Dale: Fielding, Wiseman, T Kennedy, McArdle, Stanton, Toner, J Kennedy, Jones, Thompson, O'Grady, Dagnall.
Chesterfield: Lee, Whing, Austin, Breckin, Picken, Demontagnac, Gray, Allott, Small, Rundle, Conlon.
Referee: Peter Quinn (Cleveland). Assistant Referees: Richard Clark (Northumberland) & Andy Madley (West Yorkshire). Fourth Official: David Plowright (Nottinghamshire).
Attendance: 4,471 (914 Dale fans).
