A Marc Richards brace helped Chesterfield to a first win in four games as three goals in eight minutes saw off Northampton.
Jay O'Shea celebrated his permanent deal by finishing from 10 yards after combining with Danny Whitaker.
A Clarke Carlisle error allowed Richards to fire low into the net, before Tendayi Darikwa released the striker to slot past Lee Nicholls.
Northampton came close to a consolation when Chris Hackett hit the crossbar.
VIEW FROM THE DRESSING ROOM
Chesterfield manager Paul Cook told BBC Radio Sheffield:
"We are delighted - it felt like two games we lost in a quick couple of days to Accrington and Wycombe.
"We're a club that expect to win football games and we've worked hard all week.
"The lads were a credit today, we had loads of good players, loads of good performances and it was a very good win against a very good side.
"We looked really good on the break and counter-attacking."
Northampton Town manager Aidy Boothroyd told BBC Radio Northampton:
"It's a missed opportunity. When you go on a little run, you build a reputation.
"The team that you play against up their game because they're frightened of you.
"I'm thoroughly disappointed because we never started for 30 minutes. It was unacceptable. We were mentally lazy - they were up for it and we were complacent.
"We got a hiding, we have to take it but we're better than that."
Live Text Commentary
Full Time The game is over, as the referee blows his whistle.90:00 +2:09
Free kick awarded for a foul by Sam Togwell on Ishmel Demontagnac. Chris Hackett has a direct shot on goal from the free kick, save by Tommy Lee.90:00 +1:41
Handball decision goes against Ishmel Demontagnac. Tommy Lee takes the direct free kick.90:00 +0:09 Substitution
Substitution Jonathan Wafula joins the action as a substitute, replacing James O'Shea.89:44
Chris Hackett is flagged offside by the assistant referee. Direct free kick taken by Tommy Lee.88:41
The offside flag is raised against Jake Robinson. Free kick taken by Tommy Lee.87:48
Corner taken by Danny Whitaker from the left by-line to the near post, clearance made by Ben Tozer.87:25
Short corner taken by Danny Whitaker from the left by-line.86:22
The referee blows for offside. Lee Nicholls takes the free kick.84:29 Substitution
Substitution Jack Lester joins the action as a substitute, replacing Marc Richards.84:12
Chris Hackett takes a shot from just inside the penalty box which clears the bar.81:33 Substitution
Substitution (Northampton) makes a substitution, with Ishmel Demontagnac coming on for Ben Harding.81:33
The assistant referee signals for offside against Clive Platt. Tommy Lee restarts play with the free kick.79:43
Jake Robinson is caught offside. Free kick taken by Liam Cooper.79:11
Luke Guttridge gives away a free kick for an unfair challenge on Danny Whitaker. Liam Cooper takes the direct free kick.78:35
Effort on goal by Danny Whitaker from deep inside the area goes harmlessly over the bar.76:41
Outswinging corner taken by Danny Whitaker from the right by-line played to the near post.75:04 Substitution
Substitution Mark Randall is brought on as a substitute for Craig Clay.75:04
Free kick awarded for an unfair challenge on Nathan Smith by Lewis Hornby. Tommy Lee restarts play with the free kick.72:59 Substitution
Substitution Lewis Hornby is brought on as a substitute for Adebayo Akinfenwa.
The referee blows for offside. Free kick taken by Lee Nicholls.71:56
Foul by Sam Togwell on Chris Hackett, free kick awarded. Shot comes in from Ben Harding from the free kick, Tommy Lee makes a save.69:52
Chris Hackett produces a shot from just outside the area that bounces off the post.69:16
Craig Clay concedes a free kick for a foul on Ben Harding. Free kick taken by Clarke Carlisle.67:11 Booking
Booking The referee shows Jake Robinson a yellow card for unsporting behaviour.67:06
Jake Robinson concedes a free kick for a foul on James O'Shea. Liam Cooper takes the free kick.64:22
Shot by Clive Platt from deep inside the penalty area misses wide to the left of the target.63:32
The official flags Adebayo Akinfenwa offside. Tommy Lee takes the direct free kick.62:32
Sam Hird fouled by Joe Widdowson, the ref awards a free kick. Tommy Lee takes the free kick.61:00
The assistant referee signals for offside against Chris Hackett. Tommy Lee restarts play with the free kick.60:29
Marc Richards takes a shot. Save made by Lee Nicholls.58:16
Effort on goal by Adebayo Akinfenwa from just inside the penalty box goes harmlessly over the target.56:00
Tommy Lee fouled by Adebayo Akinfenwa, the ref awards a free kick. Free kick taken by Tommy Lee.55:04
Marc Richards takes a shot. Save by Lee Nicholls.53:07
Adebayo Akinfenwa handles the ball and concedes a free kick. Sam Hird takes the free kick.51:28
Inswinging corner taken right-footed by Danny Whitaker, Clarke Carlisle manages to make a clearance.50:49
Free kick awarded for an unfair challenge on Adebayo Akinfenwa by Liam Cooper. Lee Nicholls restarts play with the free kick.50:07
Corner taken right-footed by Danny Whitaker from the right by-line, clearance by Adebayo Akinfenwa.45:44
Chris Hackett takes the inswinging corner, clearance made by Sam Togwell.45:01
The second half begins.45:00 +2:14 Half time
Half Time The half-time whistle blows.45:00 +1:36
The assistant referee signals for offside against Kelvin Langmead. Direct free kick taken by Tommy Lee.44:26
Danny Whitaker challenges Joe Widdowson unfairly and gives away a free kick. Clarke Carlisle takes the free kick.43:00 +0:14 Booking
Booking Clarke Carlisle receives a caution.42:28
Shot by James O'Shea from a long way out goes over the crossbar.40:26
Adebayo Akinfenwa gives away a free kick for an unfair challenge on Craig Clay. Liam Cooper takes the direct free kick. Craig Clay takes a shot. Save by Tommy Lee.34:41
Shot by James O'Shea from just outside the area goes over the net.33:05
Marc Richards gives away a free kick for an unfair challenge on Clarke Carlisle. Direct free kick taken by Lee Nicholls.32:16
Shot on goal by Marc Richards from just inside the area goes over the target.30:06
Long distance effort from Luke Guttridge misses to the left of the goal.27:31
Adebayo Akinfenwa takes a shot. Save by Tommy Lee.24:30
Assist on the goal came from Tendayi Darikwa.24:30 Goal scored
Goal! - Marc Richards - Chesterfld 3 - 0 Northamp'n Goal scored by Marc Richards from inside the box to the bottom right corner of the goal. Chesterfield 3-0 Northampton.21:49
Corner taken by Danny Whitaker from the right by-line, Close range header by Neal Trotman goes over the crossbar.18:42
The assist for the goal came from James O'Shea.18:42 Goal scored
Goal! - Marc Richards - Chesterfld 2 - 0 Northamp'n Marc Richards grabs a goal from inside the area to the bottom left corner of the goal. Chesterfield 2-0 Northampton.17:08
Assist by Danny Whitaker.17:08 Goal scored
Goal! - James O'Shea - Chesterfld 1 - 0 Northamp'n Goal scored by James O'Shea from close range to the top right corner of the goal. Chesterfield 1-0 Northampton.15:51
Foul by Clive Platt on Sam Togwell, free kick awarded. Tommy Lee restarts play with the free kick.14:13
Foul by Kelvin Langmead on Marc Richards, free kick awarded. Strike on goal comes in from Marc Richards from the free kick, save by Lee Nicholls.11:18
The official flags Marc Richards offside. Direct free kick taken by Lee Nicholls.8:04
Marc Richards produces a right-footed shot from deep inside the penalty box which goes wide of the right-hand upright.6:38
Unfair challenge on Tommy Lee by Adebayo Akinfenwa results in a free kick. Direct free kick taken by Tommy Lee.5:09
The offside flag is raised against Kelvin Langmead. Tommy Lee restarts play with the free kick.4:12
Joe Widdowson fouled by Sam Hird, the ref awards a free kick. Chris Hackett crosses the ball in from the free kick.3:26
Clive Platt is caught offside. Tommy Lee restarts play with the free kick.0:04
Adebayo Akinfenwa concedes a free kick for a foul on Nathan Smith. Tommy Lee restarts play with the free kick.0:00
The ref blows the whistle to start the match.
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