Southend United dropped into the bottom four of League One, after crashing to a 3-0 defeat at Hartlepool United.
Roy O'Donovan, who had a loan spell at the Blues earlier in the season, scored all three goals to cap a hugely disappointing afternoon and a missed opportunity to get a result against their fellow strugglers in the table.
Alan McCormack went on to cap such frustrations when he was shown a red card in the closing stages of the game at Victoria Park.
Inside the opening two minutes of the match, Hartlepool were awarded a free kick on the edge of the box after McCormack bundled over O'Donovan, with Neil Austin blasting the set piece over the frame of the goal.
With the hosts applying the early pressure, it needed a vital save from Steve Mildenhall to deny Adam Boyd, as the striker hooked a 25 yard volley at goal, which had to be impressively tipped over the top.
And in the 16th minute Hartlepool opened the scoring, having caught the Southend defence flat footed.
Boyd's threaded pass from the middle of the park released an unmarked O'Donovan to go through on goal and arrow the ball beyond the on-rushing Mildenhall.
Southend looked to mount a response, with Scott Vernon dragging a shot wide of the left-hand post from the edge of the penalty area before goalkeeper Scott Flinders had to beat away a well-struck effort from distance by Simon Francis.
Yet it was Hartlepool who were celebrating again in the 32nd minute, with O'Donovan again on target.
With Boyd playing a ball over the top, Jean-Yves M'Voto simply stood still at the back believing O'Donovan was offside, but with the linesman keeping his flag down, the Irishman raced in the clear and took all the time he needed to direct a low shot past Mildenhall.
Southend reshuffled the defence at half time with left back Scott Malone replacing M'Voto and allowing Adam Barrett to move into his more natural position in the centre of defence.
It was Hartlepool who fashioned the first real chance of the second half though, with Barrett and O'Donovan getting in a tangle to allow Ritchie Jones enough space to drill a low shot wide from 15 yards.
A great chance then arrived for Francis Laurent, with Francis delivering the perfect cross from the left which was begging to be headed into the net, only for the French winger to plant the ball the wrong side of the left-hand post.
Franck Moussa came close when drilling a long range shot goalwards which deflected off Antony Sweeney and flashed just wide of the target before Vernon headed over from the resultant corner.
Time was running out for Southend to get themselves back into the match, as O'Donovan shot wide in search of his hat trick.
Southend's day then went from bad to worst eight minutes from time when McCormack was shown a second yellow card for a late tackle on Andy Monkhouse and sent off.
Francis did strike the post in injury time, but it was O'Donovan who went on to have the last word when easily escaping his marker to rifle a low finish out of Mildenhall's reach.
For the Blues it was an afternoon to forget ahead of a run of three consecutive home games where picking up points could not be more crucial - starting against Exeter City next Saturday.
Southend: Mildenhall, Francis, M'Voto (Malone 46), Baldwin, Barrett, Laurent, McCormack, Moussa, Scannell, Paterson (Spencer 73), Vernon.
Hartlepool: Flinders, Austin, Collins, Liddle, Hartley, Jones (Brown 63), Sweeney, Gamble (Humphreys 70), Monkhouse, O'Donovan, Boyd (Behan 80).
