Butler sent off as Blues are beaten
Pompey suffered the Boxing Day blues as they crashed to defeat in front of the biggest Fratton crowd of the season.
Frankie Sutherland curled home an impressive opener to give AFC Wimbledon an early lead.
And Matt Tubbs was then handed a belated Christmas present, with some sloppy defending allowing the striker to double the advantage.
The Blues did look brighter after the break, but the contest was effectively ended by Dan Butler’s dismissal for a second bookable offence.
Andy Awford made two changes from the side that drew at Cheltenham before Christmas.
Adam Webster replaced Joe Devera at right-back, while Craig Westcarr came in for Nigel Atangana just behind lone striker Ryan Taylor.
Pompey started brightly, with Jed Wallace and Lee Holmes combining to create an early opening that was just out of reach for Taylor.
But the Dons soon started to make their mark and Adam Barrett tried an acrobatic volley that flew narrowly over.
They did take the lead on nine minutes, however, when Sutherland – who had a brief spell on loan at Fratton Park in 2013 – curled a 25-yard effort into the top corner.
Pompey soon had a chance to grab an equaliser, but Taylor’s angled effort came back off the post.
The visitors immediately added insult to injury by doubling their advantage on 17 minutes.
Butler was booked for hauling down Tubbs and Barry Fuller caught the Blues napping with a quick free-kick.
Tubbs latched onto the ball and showed why he has been so prolific this season by stroking the ball into the bottom corner.
The Fratton faithful were, unsurprising, growing frustrated and their mood was not helped by Pompey continuously gifting their opponents possession.
Taylor thought he should have been awarded a penalty on 33 minutes when he went down in the box under pressure from Barrett, but referee Charles Breakspear disagreed.
Holmes then tested the handling of AFC Wimbledon stopper James Shea with a fierce effort from distance.
But it was still the visitors looking more likely to score, with some frantic defending needed to prevent them extending their advantage.
It was not until stoppage-time when the Blues finally clicked into gear and Shea made a fine stop to keep out Taylor’s fierce close-range strike.
Pompey came close again from the resulting corner, but the Dons were able to hack the ball to safety to preserve their two-goal advantage at the break.
Half Time: Pompey 0 AFC Wimbledon 2
Awford made a switch at the start of the second half, with Holmes making way for Nigel Atangana.
That also saw a change of system to match AFC Wimbledon’s diamond midfield, with Wallace at the tip behind Westcarr and Taylor.
Pompey looked threatening early on with a series of dangerous balls that caused some nervy moments in their opponents’ box.
But the Dons were still looking dangerous themselves and Jones had to save at Tubbs’ feet after Fuller had done well to find his team-mate in space.
The Blues were at least showing some urgency as they tried to force an opening and test the under-worked Shea.
Westcarr laid the ball off to Danny Hollands on 59 minutes, but the skipper’s shot was deflected behind.
Butler then did well down the left to burst into the box and send in a cross, only for Robinson to make a mess of his attempt.
And there was a glorious opportunity for Wallace, who volleyed wide from 10 yards following good build-up from Westcarr and Taylor.
But the hosts were given a mountain to climb when they were reduced to 10 men on 69 minutes.
Butler went in late on George Francomb and was shown a second yellow card – and subsequent red – by Breakspear.
Awford still had to go for it, though, and threw on Andy Barcham for Hollands in an attacking move.
But the Blues were almost caught out at the back on 80 minutes, with Jones coming to the rescue to deny Adebayo Azeez.
And the Dons comfortably saw out the final few minutes to take all three points with them back up the A3.
Pompey (4-2-3-1): Jones; Webster, Robinson, Whatmough, Butler; Bean, Hollands (c) (Barcham 75); Wallace, Westcarr, L.Holmes (Atangana 46); Taylor
Sent off: Butler (two yellow cards)
Booked: Robinson, Westcarr
Subs not used: Poke, Devera, Chorley, Shorey, Storey
AFC Wimbledon (4-diamond-2): Shea; Fuller (c), Goodman, Barrett, Kennedy; Francomb, Bulman, Rigg (Pell 71), Sutherland; Azeez, Tubbs (Oakley 85)
Goals: Sutherland 9, Tubbs 17
Booked: Bulman
Subs not used: McDonnell, Bennett, Harrison, Nicholson, Fitzpatrick
Referee: Charles Breakspear
Attendance: 17,558 (968 away fans)