Pompey 0 Chesterfield 2
A couple of late goals cruelly denied 10-man Pompey a point against high-flying Chesterfield.
The big talking point came late in the first half when David Connolly, after seeing his appeals for a penalty turned down, clashed with Sam Hird and was sent off.
The Blues looked comfortable after that incident, however, and enjoyed the best chances to score.
But they were undone by a couple of sucker-punches in the closing stages as both Arnand Gnanduillet and Tendayi Darikwa came off the bench to score.
Guy Whittingham made five changes from the side that drew 2-2 at Mansfield the previous week.
John Sullivan, Yassin Moutaouakil, Danny East, Johnny Ertl and Ricky Holmes all returned to the side.
Phil Smith, Bondz N’Gala, Romain Padovani and Jed Wallace dropped to the bench, while Marcos Painter was out with a hamstring injury.
Pompey made a bright start and it took a brilliant block from Hird to keep out Patrick Agyemang’s fierce goalbound effort.
Holmes then picked out Devera from the resulting corner, but the centre-back was unable to guide his header on target.
But it was the visitors who had the ball in the back of the net on eight minutes, although Marc Richards was offside when he collected Gary Roberts’ through ball and slotted past Sullivan.
The Blues keeper then made an instinctive stop to deny Jay O’Shea from close range, with Devera on hand to hack clear the loose ball.
Connolly thought he should have won a penalty at the other end after tangling with Liam Cooper, but referee Steve Bratt remained unmoved.
Pompey were certainly looking stronger going forward than at the back and Roberts beat three players to a ball into the box before laying it off for Richards to fire wide on 30 minutes.
Both sides looked capable of breaking the deadlock and Ertl saw his 20-yard drive deflected narrowly wide following some fine build-up play in and around the Spireites box.
Chesterfield keeper Tommy Lee then almost dropped a fine Moutaouakil cross at the feet of Andy Barcham, but recovered to grab the ball at the second attempt.
Cooper and Connolly tangled in the box again on 36 minutes with the striker appearing to be tripped as he went past his opponent, but again Bratt was not interested.
Connolly was livid at the decision and an altercation with Hird that left the Chesterfield defender lying on the turf saw Pompey’s skipper shown a straight red card.
Half Time: Pompey 0 Chesterfield 0
Pompey fans showed plenty of black humour early in the second half when a refereeing decision went in their favour and they responded with a standing ovation.
Bratt was still at the centre of attention on 56 minutes when Barcham was the next player to feel he had been fouled in the box.
Whittingham made his first change just past the hour mark, with Ryan Bird replacing Agyemang up front.
Chesterfield also made attacking switches as, despite their numerical advantage, they were not troubling the Blues.
The tireless Holmes was then withdrawn on 74 minutes, with Wallace taking up position wide on the right.
And Wallace immediately impressed, beating his man down the right and swinging in a superb cross that Lee did well to claim.
Sonny Bradley then stole possession and embarked on mazy run, travelling half the length of the pitch before seeing his shot saved.
Lee also kept out Barcham’s follow-up at point-blank range, with the ball ricocheting off Bird and flying inches past the post.
Pompey were flying now and Wallace again saw his cross cut-out by Lee following more good work on the right.
But Chesterfield grabbed the winner with their first chance of the half as Eoin Doyle swung the ball into the box and Gnanduillet rose highest to head home.
Bird might have salvaged a point for Pompey late on, but his low shot flew narrowly past the post.
Instead the visitors made sure of victory in stoppage-time with Darikwa driving a shot past Sullivan.
Pompey (4-4-2): Sullivan; Moutaouakil, Devera, Bradley, East (Craddock 88); Holmes (Wallace 74), Ertl, Ferry, Barcham; Agyemang (Bird 64), Connolly (c)
Sent off: Connolly
Subs not used: Smith, N’Gala, Butler, Padovani
Chesterfield (4-2-3-1): Lee; Talbot (c), Hird, Cooper, Smith (Gnanduillet 71); Morsy, Ryan; O’Shea (Darikwa 84), Roberts, Humphreys; Richards (Doyle 64)
Goals: Gnanduillet 87, Darikwa 90+2
Subs not used: Chapman, Edwards, Devitt, Togwell
Referee: Steve Bratt
Attendance: 15,999 (957 Chesterfield fans)