Liverpool - Dirk Kuyt scored a hat-trick to blow the Premier League title race wide open as Liverpool cruised to a 3-1 win over leaders Manchester United at Anfield on Sunday.
United went into the game knowing that victory would earn them a six-point lead over nearest rivals Arsenal at the summit with nine games remaining.
But Kuyt's treble condemned Sir Alex Ferguson's side to back-to-back Premier League defeats for the first time in two years after their midweek loss at Chelsea.
United are locked on 18 domestic league titles with Liverpool but the Merseyside club were clearly in no mood to help their bitter rivals towards a record 19th success.
Kuyt put Liverpool in control with two goals in five minutes towards the end of the first half and he scored his third in the 65th minute before Javier Hernandez's late effort for United.
And Liverpool, who climb to sixth in the table, were able to give their ?35 million signing Andy Carroll his long-awaited debut as the striker, fit after a thigh injury, came on for the final 15 minutes.
Liverpool boss Kenny Dalglish said: "The players deserved that for the discipline, application and pride shown in themselves and the club.
"It's been a tough season, it's not finished yet but this has been the highest point so far for our supporters.
"It always matters who the opposition are, because you're not going to get too many opponents who are as good as Manchester United. We deserved to win, no doubt."
Ferguson went into this game leading Dalglish 7-4 ahead of the 20th league meeting between the two Scottish managers.
Ferguson also won the tactical battle between the pair when United defeated Liverpool 1-0 in the FA Cup two months ago in what was Dalglish's first match back since returning to the Anfield hot seat.
But there was revenge in the Merseyside air as Kuyt's first half double put the hosts in command.
United were missing their first-choice central defensive pairing of Nemanja Vidic, who was suspended, and Rio Ferdinand, who was injured, forcing Ferguson to field Wes Brown alongside Chris Smalling.
And the inexperienced partnership was immediately tested as Luis Suarez, twice, and Maxi Rodriguez both had efforts before Dimitar Berbatov was denied by the post in what was United's first serious attack in the 16th minute.
Up until that moment the game had been fairly even but the hosts took control in an explosive finish to the half.
Kuyt's opening goal in the 34th minute was down to the brilliance of Suarez, the Uruguay forward leaving Rafael da Silva and Michael Carrick chasing shadows before squaring for the Netherlands international to score his first ever goal against United.
His second followed five minutes later courtesy of an error by Nani, the Portuguese winger heading into the path of Kuyt to nod past Edwin van der Sar and double his side's lead from close range.
Yet what had been a compelling first half took an ugly turn as both sides were fortunate to retain 11 men.
Liverpool defender Jamie Carragher was extremely fortunate to escape with a caution for a nasty 39th minute challenge on Nani, the United player climbing off the floor to remonstrate with the referee before being carried off on a stretcher after collapsing.
Then Rafael, who was booked, was lucky to stay on after his X-rated challenge on Lucas in the 44th minute.
United desperately needed a goal early in the second half and they nearly got one when Berbatov's 58th minute header was heading for the net only to be chested off the line by Raul Meireles.
But Liverpool survived and seven minutes later confirmed their fifth win in nine Premier League games since Dalglish returned when Kuyt completed his hat-trick.
Once again Suarez was again involved as his curling free-kick was beaten away by Van der Sar into the path of Kuyt to become the first Liverpool player since Peter Beardsley in 1990 to score three against United.
There was still time for Carroll to come off the bench and make his long-awaited debut in the 74th minute before substitute Hernandez scored in stoppage time with a glancing header.