Fernando Torres and substitute David Ngog left Manchester United reeling as Liverpool brilliantly halted their four-match losing streak.
Liverpool manager Rafael Benitez had said prior to the match that one win would change everything, and what a result his team delivered to ease the pressure on the Spaniard.
The champions were eventually beaten after a stunning performance of defiance from the home side.
In this cracking Barclays Premier League battle, Liverpool restored their pride with a victory over, for them, the best opponents possible.
Torres forced his injured frame through the match and grabbed his ninth goal of the campaign midway through the second half to get Liverpool really firing.
Ngog hit the second in stoppage-time, with the match at boiling point. United had by that stage lost defender Nemanja Vidic to his third red card in successive matches against Liverpool.
Javier Mascherano saw red too, but it was Liverpool who inflicted the second league defeat of the season on United to restore faith among their fans.
The atmosphere was electric, the noise deafening, as Liverpool set about trying to restore their battered reputation.
angled effort
Evra was booked after two trips on Torres in as many minutes, and from the free-kick Fabio Aurelio sent in a curled effort that Edwin van der Sar clawed away. It went straight to Dirk Kuyt, whose follow-up was also saved by his Dutch countryman.
Then Lucas dispossed Paul Scholes and gave Kuyt another chance, this one guided wide of the far post.
Rooney, who had seen one effort disallowed for offside, rose to met an Antonio Valencia cross, but his header was held low to his right by Jose Reina.
United had better possession and hit Liverpool with pace and slick movement, but Van der Sar was again needed to plunge to his right to keep out an Aurelio header from Yossi Benayoun's cross.
Kuyt should have scored early in the second period when he was played in by Johnson, but he chose to pass rather than blast an angled effort, and the chance was lost.
Then Benayoun's touch sent Torres away on the right, but his lack of pace following his groin problem did not see him shake off Rio Ferdinand, and again the opening went begging.
It then needed a block from Johnson on the far post to keep out Rooney's header from Giggs' free-kick.
good friend
But Liverpool were growing in confidence and they grabbed the lead after 65 minutes. Benayoun's pass sent Torres beyond Ferdinand, onside only by inches.
The Spaniard was not going to be denied this time. He held off the England centre-back and lashed a shot into the roof of the net. The roof almost came off Anfield too.
Vidic was booked for a foul on Torres, and then after 80 minutes Torres could run no more and Ngog took his place.
Valencia saw a cross-shot clip the Liverpool bar and substitute Michael Owen was searching for any inch of space. He almost had a chance when he chased a throughball, only to be hauled down by his good friend Jamie Carragher. The Liverpool skipper was booked.
With just a minute of normal time left, Vidic pulled down Kuyt as the Dutchman raced into an empty half. Red followed a second yellow, and the Serbian was sent off for the third successive match against Liverpool.
Three minutes into added time Mascherano was also sent off for a challenge on Van der Sar, the Argentinian's second yellow-card offence.
Then came the killer blow to United. Liverpool broke from deep defence, Lucas delayed his pass to sent Ngog away on his own and the striker slid the second past Van der Sar. Anfield, and Benitez, could finally celebrate.
