Colchester capitalised on Portsmouth's early defensive frailties to earn their first away league win since October.
The U's were ahead after just two minutes when Gavin Massey turned home Freddie Sears's cross, but Jed Wallace volleyed home an equaliser soon after.
Pompey debutant Sam Sodje then felled Sears in the box, who scored the penalty himself before Massey struck the visitors' third after 20 minutes.
James Keene blasted home to reduce the deficit, but the U's held on.
VIEWS FROM THE DRESSING ROOM
Portsmouth caretaker manager Guy Whittingham told BBC Radio Solent:
"There was no commitment to anything, you can't excuse that in a football game.
"It's what football is about, it's what makes winners and losers and we had none of that in the first half.
"We try to tell them (the players) that the fans will support you, all you've got to do is be committed.
"They'll give and take on the losing front but if you don't commit that's when they're not happy."
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Saturday, 2 February 2013
Sears (pen) 16
Attempts on target
Attempts off target
90:00+6:34 The final whistle is blown by the referee.
90:00+4:30 Free kick taken by Drey Wright.
90:00+4:30 Booking Jabo Ibehre goes into the book for unsporting behaviour.
90:00+4:18 Liam Walker concedes a free kick for a foul on Jabo Ibehre.
90:00+3:50 D Butler gives away a free kick for an unfair challenge on Drey Wright. Free kick taken by David Wright.
90:00+0:52 The assistant referee signals for offside against Ashley Harris. Direct free kick taken by Sam Walker.
89:40 Gavin Massey has an effort at goal from the edge of the box that misses to the right of the target.
88:13 Gabor Gyepes challenges Jabo Ibehre unfairly and gives away a free kick. Brian Wilson restarts play with the free kick.
87:21 The ball is swung over by John White.
85:35 Substitution Andy Bond comes on in place of Billy Clifford.
85:08 Adam Reed crosses the ball, Magnus Okuonghae makes a clearance.
82:39 Effort from 35 yards by David Wright missed to the right of the net.
81:12 Substitution Drey Wright replaces George Porter.
80:36 D Butler takes a inswinging corner from the right by-line played to the near post, Gavin Massey makes a clearance.
79:31 Ashley Harris crosses the ball in from the free kick, clearance made by Sam Walker.
79:31 Booking Marcus Bean receives a yellow card.
79:22 Foul by Marcus Bean on Jed Wallace, free kick awarded.
78:15 Booking The referee cautions George Porter for dissent.
78:00 Foul by George Porter on D Butler, free kick awarded. Simon Eastwood takes the direct free kick.
75:44 Free kick awarded for a foul by Gavin Massey on Yassin Moutaouakil. Simon Eastwood takes the free kick.
74:47 Adam Reed has an effort at goal from outside the penalty box missing to the wide right of the target.
73:50 Jabo Ibehre gives away a free kick for an unfair challenge on Sam Sodje. Direct free kick taken by Simon Eastwood.
Correction - 72:49 Assist by Liam Walker.
72:49 Assist on the goal came from James Keene.
72:49 GOAL - James Keene James Keene grabs a goal from close range to the bottom left corner of the goal. Portsmouth 2-3 Colchester.
: Portsmouth 2 - 3 Colchester
72:08 Free kick awarded for an unfair challenge on Jabo Ibehre by Liam Walker. Free kick taken by David Wright.
71:49 Substitution Marcus Bean comes on in place of Freddie Sears.
71:34 James Keene produces a left-footed shot from deep inside the penalty box which goes wide of the left-hand upright.
70:58 Corner taken left-footed by Liam Walker, clearance by Josh Thompson.
70:47 Liam Walker crosses the ball, Brian Wilson manages to make a clearance.
69:44 Corner taken by Liam Walker played to the near post.
67:39 Substitution (Portsmouth) makes a substitution, with Adam Reed coming on for Shaun Cooper.
66:05 Sam Sodje has a headed effort at goal from just inside the penalty area that misses to the left of the goal.
65:44 Josh Thompson concedes a free kick for a foul on James Keene. D Butler takes the free kick.
61:51 The referee blows for offside. Free kick taken by D Butler.
61:21 Ashley Harris takes a inswinging corner.
60:45 Liam Walker takes a shot. Clearance made by Billy Clifford.
59:28 Unfair challenge on George Porter by D Butler results in a free kick. Brian Wilson takes the free kick.
58:29 James Keene concedes a free kick for a foul on Sam Walker. Sam Walker restarts play with the free kick.
57:41 Free kick awarded for an unfair challenge on Ashley Harris by Billy Clifford. Liam Walker restarts play with the free kick.
56:59 Shot from outside the area by Jed Wallace misses to the left of the goal.
53:12 Shaun Cooper takes a shot. Blocked by Brian Wilson.
53:00 Jed Wallace sends in a cross.
49:19 Corner from right by-line taken by D Butler.
48:59 Johnny Ertl has a shot on goal from outside the box which misses left.
47:19 Inswinging corner taken by Ashley Harris.
46:50 Corner taken by Ashley Harris played to the near post, clearance made by Magnus Okuonghae.
45:46 James Keene challenges John White unfairly and gives away a free kick. Sam Walker takes the direct free kick.
45:01 The referee blows his whistle to start the second half.
45:01 Substitution Liam Walker on for David Connolly.
45:00+2:09 The half-time whistle blows.
45:00+0:24 Johnny Ertl concedes a free kick for a foul on Freddie Sears. Free kick taken by Magnus Okuonghae.
44:50 Shot by Jabo Ibehre from deep inside the penalty area misses wide to the left of the target.
38:57 Foul by George Porter on D Butler, free kick awarded. Gabor Gyepes restarts play with the free kick.
36:39 David Connolly takes a shot. Sam Walker makes a save.
36:14 Foul by Billy Clifford on Gabor Gyepes, free kick awarded. Yassin Moutaouakil takes the free kick.
34:28 Ashley Harris has an effort at goal from outside the area which misses left.
33:49 Free kick awarded for an unfair challenge on David Connolly by Josh Thompson. D Butler restarts play with the free kick.
31:33 Handball decision goes against Gavin Massey. Free kick taken by Simon Eastwood.
27:59 The ball is crossed by George Porter, Gavin Massey produces a right-footed shot from close range which goes wide of the left-hand
26:05 Substitution Gabor Gyepes replaces Ricardo Rocha.
24:12 Free kick awarded for an unfair challenge on James Keene by Magnus Okuonghae. D Butler takes the direct free kick.
23:11 Unfair challenge on Freddie Sears by Jed Wallace results in a free kick. Direct free kick taken by Billy Clifford.
21:41 Jabo Ibehre takes a shot. Ricardo Rocha gets a block in.
Correction - 19:46 GOAL - Gavin Massey Gavin Massey grabs a goal from close range to the bottom left corner of the goal. Portsmouth 1-3 Colchester.
: Portsmouth 1 - 3 Colchester
19:46 GOAL - Gavin Massey Goal scored by Gavin Massey from inside the six-yard box to the bottom left corner of the goal. Portsmouth 1-3 Colchester.
: Portsmouth 1 - 3 Colchester
19:06 Jabo Ibehre sends in a cross, Effort from close range by Gavin Massey goes wide left of the target.
18:01 Free kick awarded for a foul by Yassin Moutaouakil on Jabo Ibehre. Billy Clifford takes the direct free kick.
15:28 GOAL - Freddie Sears Placed penalty scored by Freddie Sears. Portsmouth 1-2 Colchester.
: Portsmouth 1 - 2 Colchester
14:35 Unfair challenge on Freddie Sears by Sam Sodje results in a Penalty.
Correction - 12:17 The ball is swung over by Yassin Moutaouakil.
12:17 The ball is sent over by Yassin Moutaouakil.
9:09 Shaun Cooper challenges George Porter unfairly and gives away a free kick. Direct free kick taken by Brian Wilson.
6:28 Outswinging corner taken by Billy Clifford.
4:07 Assist on the goal came from D Butler.
4:07 GOAL - Jed Wallace Jed Wallace finds the net with a goal from close in to the bottom right corner of the goal. Portsmouth 1-1 Colchester.
: Portsmouth 1 - 1 Colchester
3:52 Inswinging corner taken by D Butler,
1:48 Assist on the goal came from Freddie Sears.
1:48 GOAL - Gavin Massey Gavin Massey finds the net with a goal from close range to the bottom right corner of the goal. Portsmouth 0-1 Colchester.
: Portsmouth 0 - 1 Colchester
0:29 David Connolly fouled by Magnus Okuonghae, the ref awards a free kick. Direct free kick taken by Ashley Harris.
0:00 The referee gets the match started.
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