Wigan heaped further misery on Kenny Dalglish's Liverpool and increased their chances of beating relegation with a sensational 2-1 win at Anfield.
Gary Caldwell was the unlikely hero, slotting in the winner on 63 minutes after Luis Suarez had cancelled out Shaun Maloney's first-half penalty.
It is the first time the Latics have won on Liverpool's turf, and it puts them within one point of safety with eight games remaining.
For Liverpool, questions will be asked of manager Kenny Dalglish, who has suffered back-to-back defeats in a nightmare week for the Reds.
The statistics for Liverpool are damning; five defeats in the last six Premier League matches - 10 losses for the season - and only two wins in 2012 do not make happy reading for Dalglish.
He is already facing some difficult questions and had he not already won the Carling Cup and progressed to the semi-finals of the FA Cup the situation would be even more uncomfortable for the Scot.
Even a late debut for 17-year-old reserves prodigy Raheem Sterling could not lift the gathering gloom at Anfield.
But as poor as Liverpool were credit must go to Wigan who stuck to their task and, unlike in recent weeks when they have been unable to hold on to good positions, they bounced back from Suarez's equaliser to claim a vital victory.
The early signs were that it was going to be another frustrating afternoon for the home side as nothing they tried came off with passes falling short, going astray or players being caught in possession.
Wigan, by nature of their perilous position, were hungrier and more determined and when Victor Moses got past Jose Enrique, albeit by virtue of a surreptitious handball, Martin Skrtel blocked the winger's shot.
Steven Gerrard's bobbled shot wide was indicative of Liverpool's play while Stewart Downing fired a half-volley just wide of the far post after exchanging passes with Suarez.
Wigan had not threatened Jose Reina's goal until just before the half hour when Skrtel, in trying to clear Jamie Carragher's aimless header, caught Moses in the face.
Referee Lee Mason pointed to the spot and after a couple of minutes' delay for Moses to receive treatment Maloney tucked away the penalty.
Suarez finally forced Ali Al Habsi into a save five minutes before half-time with a 25-yard curling effort before another Gerrard shot was palmed behind.
Andy Carroll replaced Jordan Henderson, who had been the primary focus of Anfield's annoyance, for the second half but it was Gerrard and Suarez - Liverpool's two most reliable attacking forces - who combined for the equaliser just two minutes after the restart.
Suarez moved the ball out to his captain on the right of the penalty area and continued his run to convert the return with a shot across Al Habsi.
The Uruguay international should have doubled his tally in the 53rd minute but handled the ball over the line from Skrtel's downward header, and was penalised with a yellow card following the incident.
The Reds were made to pay in the 63rd minute when James McCarthy's shot from Carroll's defensive header deflected off Jamie Carragher to Caldwell.
Showing composure not usually befitting a centre-back in front of goal he side-stepped Carroll to fire past Reina.
With seven minutes remaining Sterling, signed from QPR for £600,000 just over two years ago, was given his chance.
The youngster had one good run along the edge of the 18-yard box which almost set up a shooting opportunity but it was asking a lot for the teenager to have an impact on a game in which a number of his vastly more experienced team-mates had failed to impose themselves.
At the final whistle Wigan's small band of travelling fans were ecstatic but the pervading feeling from those who remained at Anfield until the final whistle was one of growing discontent.