Liverpool rekindled the title race on Saturday with a 4-1 mauling of Premier League leaders Manchester United at Old Trafford.
After their midweek thrashing of Real Madrid in the Champions League, Liverpool responded to falling behind to a Cristiano Ronaldo penalty with a sensational display to seal a league double over their bitter rivals.
Fernando Torres and a Steven Gerrard spot kick edged Liverpool in front by halftime and then Fabio Aurelio curled in a 77th minute free kick to make it 3-1 after United defender Nemanja Vidic had been sent off.
Substitute Andrea Dossena lobbed a fourth in stoppage time to stun the vast majority inside Old Trafford and end United's 16-match unbeaten run in the league.
United still lead the table by four points from Liverpool and have a game in hand but their poor performance will give their closest pursuers hope that they can be caught.
"It was a great team performance from back to front," Liverpool captain Steven Gerrard told Sky Sports. "It was a magnificent win. It's not very often you see Man United get beaten 4-1 at home."
The match turned on a dreadful error by Serb defender Vidic, a rock at the heart of a United defence that recently went 14 league matches without conceding a goal.
United appeared to be in control when Ronaldo converted a penalty after Liverpool keeper Pepe Reina had brought down Park Ji-sung on the edge of the area.
Five minutes later, an aimless long pass out of defence appeared to be comfortable for Vidic but he seemed to get caught in two minds and as he stumbled, Torres stole in to place a low finish past Edwin van der Sar.
Liverpool began playing fluently and they went ahead just before the break when Patrice Evra was caught by the pace of Gerrard's burst into the area and clipped the England midfielder's ankles as he tried to recover.
Gerrard got up to beat Van der Sar low to his left with the penalty and Liverpool did not look back.
United manager Alex Ferguson sent on Paul Scholes, Ryan Giggs and Dimitar Berbatov, all rested after Wednesday's defeat of Inter Milan, with around 15 minutes to go but the home side's hopes of a fightback were ruined when Vidic bundled over the goalbound Gerrard and was red-carded.
Aurelio curled the free kick past a motionless Van der Sar and Liverpool's fans were euphoric when Dossena latched on to a huge Reina clearance to calmly lob into an empty net.