Late goals from Armand Gnanduillet and Tendayi Darikwa gave Chesterfield victory over 10-man Portsmouth and sent them top of League Two.
Pompey were reduced to 10 men when skipper David Connolly was given a straight red card for an off-the-ball incident with Sam Hird.
Gnanduillet headed home Eoin Doyle's cross from the right for 1-0.
Darikwa then produced a super strike across Pompey keeper John Sullivan in stoppage time to seal the victory.
VIEW FROM THE DRESSING ROOM
Portsmouth manager Guy Whittingham told BBC Radio Solent:
"The players have given absolutely everything. I couldn't ask any more of them whatsoever.
"They've battled and they've fought and they've even got chances that second half; playing against a very good Chesterfield side who will be up there or thereabouts I think they've given everything they can for us.
"I thought we got a goal when Sonny Bradley went through; how we haven't scored I don't know, from that. Of course you're disappointed, there were two penalties we should have had. Where he's taken out David Connolly, their manager's saying it's a stonewall penalty."
On Connolly penalty shout and subsequent red card : "David's frustrated, I didn't see what happened. David's apologised, he says it was out of order for him to do it, but he was still wound up by the decisions from earlier."
Chesterfield manager Paul Cook tells BBC Radio Sheffield:
"The game swung on a couple of big decisions, the penalty (shout) for Portsmouth in the first half.
"It looked a penalty... and then David Connolly's got involved and suddenly he's been sent off.
"Second half, we never played well. We never moved the ball quickly enough, the pitch is very dry and we were making bad decisions.
"But to come to a place like this and get a result you have to give the lads credit, it's a fantastic result, not a fantastic performance, but certainly a fantastic result."
Live Text Commentary
Full Time The final whistle is blown by the referee.90:00 +4:49
Corner from the left by-line taken by Jed Wallace.90:00 +3:43
Clearance made by Tendayi Darikwa.90:00 +3:32
Corner taken by Jed Wallace from the right by-line.90:00 +2:00
Assist by Armand Gnanduillet.90:00 +2:00 Goal scored
Goal! - Tendayi Darikwa - Portsmouth 0 - 2 Chesterfld Tendayi Darikwa scores with their right foot. Portsmouth 0-2 Chesterfield.89:10
Ryan Bird takes a shot and missed to the left of the goal.88:22
Free kick crossed by Yassin Moutaouakil.88:10 Substitution
Substitution (Portsmouth) makes a substitution, with Tom Craddock coming on for Danny East.87:54
Free kick awarded for a foul by Gary Roberts on Yassin Moutaouakil.86:21
Assist by Eoin Doyle. Assist by Eoin Doyle.86:21 Goal scored
Goal! - Armand Gnanduillet - Portsmouth 0 - 1 Chesterfld Armand Gnanduillet scores. Portsmouth 0-1 Chesterfield.83:43 Substitution
Substitution (Chesterfield) makes a substitution, with Tendayi Darikwa coming on for James O'Shea.82:26
Shot by Eoin Doyle went wide of the left-hand post.81:44
Jed Wallace sends in a cross.81:17
Corner from the right by-line taken by Gary Roberts.80:09
Sonny Bradley takes a shot. Tommy Lee catches the ball.79:48
The ball is sent over by Jed Wallace.74:58
The ball is delivered by Yassin Moutaouakil.74:48
Corner from the right by-line taken by Jed Wallace.
Free kick taken by John Sullivan.73:47 Substitution
Substitution Jed Wallace is brought on as a substitute for Ricky Holmes.73:31
The assistant referee signals for offside against Eoin Doyle.71:15
John Sullivan takes the free kick.70:56
Armand Gnanduillet is caught offside.70:28 Substitution
Substitution Armand Gnanduillet on for Nathan Smith.69:06
Sam Hird manages to make a clearance.69:01
Corner from the left by-line taken by Ricky Holmes.68:09
John Sullivan takes the free kick.67:40
Drew Talbot challenges Danny East unfairly and gives away a free kick.66:05
Clearance by Sonny Bradley.66:01
The ball is crossed by James O'Shea.64:21
Free kick taken by John Sullivan.64:04 Substitution
Substitution Marc Richards leaves the field to be replaced by Eoin Doyle.63:10 Substitution
Substitution Ryan Bird is brought on as a substitute for Patrick Agyemang.62:48
Nathan Smith gives away a free kick for an unfair challenge on Ricky Holmes.58:37
The ball is crossed by Drew Talbot.54:47
John Sullivan restarts play with the free kick.54:18
James O'Shea goes into the book.54:18 Booking
James O'Shea concedes a free kick for a foul on Ricky Holmes.52:38
Jimmy Ryan restarts play with the free kick.52:26
James O'Shea fouled by Johnny Ertl, the ref awards a free kick.51:44
Tommy Lee restarts play with the free kick.51:29
Ricky Holmes gives away a free kick for an unfair challenge on Nathan Smith.51:13
John Sullivan takes the free kick.50:54
The offside flag is raised against Nathan Smith.49:42
Shot by James O'Shea went over the bar.48:46
The ball is delivered by Andy Barcham.46:51
Ricky Holmes has a direct shot on goal from the free kick.45:58
Foul by Sam Hird on Ricky Holmes, free kick awarded.45:01
The referee gets the second half underway.45:00 +4:24 Half time
Half Time The whistle is blown to end the first half.45:00 +4:19
Free kick taken by John Sullivan.45:00 +4:05
The offside flag is raised against Gary Roberts.45:00 +1:20
John Sullivan takes the free kick.45:00 +0:53
Nathan Smith delivers the ball.44:14
Shot by Gary Roberts went harmlessly over the bar.43:21
James O'Shea takes a shot and cleared the crossbar.40:15
Drew Talbot restarts play with the free kick.37:46
David Connolly sent off.37:46 Dismissal
Yassin Moutaouakil sends in a cross.34:35
Liam Cooper takes the free kick.34:27
Ricky Holmes challenges Sam Hird unfairly and gives away a free kick.33:13
A cross is delivered by Danny East.33:09
Corner taken by Ricky Holmes from the left by-line.32:44
Johnny Ertl takes the chance to get an effort at goal.29:35
Marc Richards takes a shot and went wide right of the net.25:13
Danny East manages to make a clearance.25:08
Centre by Nathan Smith.23:53
Free kick taken by Tommy Lee.23:31
David Connolly is flagged offside by the assistant referee.22:50
Clearance by Nathan Smith.22:44
Ricky Holmes crosses the ball in from the free kick.22:14
Sam Morsy concedes a free kick for a foul on Ricky Holmes.19:24
Clearance by Joe Devera.19:18
The ball is delivered by Gary Roberts.17:20
James O'Shea takes a shot. A parry by John Sullivan prevents the goal.15:38
Free kick taken by Tommy Lee.15:23
The referee blows for offside against Ricky Holmes.13:18
Free kick taken by John Sullivan.12:59
The referee blows for offside.12:08
John Sullivan restarts play with the free kick.11:44
Free kick awarded for a foul by James O'Shea on Simon Ferry.7:28
Free kick taken by John Sullivan.7:12
The assistant referee flags for offside against Marc Richards.5:07
Header at goal by Joe Devera goes over the bar.4:58
Corner taken by Ricky Holmes from the right by-line.4:14
Liam Cooper manages to make a clearance.4:04
Corner taken by Simon Ferry from the left by-line.0:48
Tommy Lee restarts play with the free kick.0:23
David Connolly is caught offside.0:00
The ref blows the whistle to begin the match.
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