Liverpool hold the advantage and have a first Wembley appearance since 1996 in their sights after a Carling Cup semi-final first-leg victory at Manchester City.
Steven Gerrard's early penalty, awarded when Stefan Savic fouled Daniel Agger, condemned City to a second successive home defeat after their FA Cup exit against Manchester United on Sunday.
It was the first time City have suffered such a fate since February 2008 and they now face a tough task to turn the tie around at Anfield in a fortnight.
There was controversy in the closing stages when Glen Johnson caught Joleon Lescott with a two-footed challenge which City manager Roberto Mancini claimed was worthy of a red card.
Gerrard's goal was fully deserved after Liverpool forced a succession of outstanding early saves from Manchester City keeper Joe Hart as Mancini's side struggled to hit their rhythm.
And when City did finally exert pressure and dominate possession after the break, Liverpool were in resilient mood at the back and rarely looked like conceding the lead their inspirational captain had given them.
City were without the two major influences of their 3-0 Premier League victory against Liverpool last week, with Kompany suspended and Yaya Toure with the Ivory Coast at the Africa Cup of Nations.
And how they missed their power and leadership with David Silva also out injured and the out-of-sorts Mario Balotelli taken off before half-time.
Liverpool, in contrast, stood firm throughout and manager Kenny Dalglish's only complaint may be that they failed to add further goals in that impressive opening burst.
They were without their own suspended spearhead Luis Suarez, but Liverpool compensated for their key absentee with greater success than City did with their missing stars.
Kompany's four-game ban for his contentious red card against United meant a place for Savic in central defence and Liverpool, with Gerrard setting the tempo, played on the Montenegrin's uncertainty to exert total superiority early on.
Only Hart stood between Liverpool and an emphatic early advantage. He plunged at Andy Carroll's feet after he turned Savic, then saved low to his left from Gerrard's skidding 25-yard shot.
He produced his best from Stewart Downing's deflected shot - but Liverpool got the lead their supremacy merited from the penalty spot after 13 minutes.
Savic was again involved with an injudicious lunge at Agger, Gerrard drilling the resulting spot-kick low into Hart's bottom right-hand corner.
Liverpool's control was complete, especially in midfield, but they lost Jay Spearing to injury when he pulled up suddenly and had to be replaced by Charlie Adam.
City, without the magical influence of Silva, were making no impression on Liverpool's defence, with Balotelli in indifferent mood and form.
He had been carrying an injury prior to kick-off and looked listless throughout, getting involved in a needless spat with Adam and looking unhappy with life in general.
Mancini had finally seen enough after 38 minutes, removing Balotelli from the action and sending on Samir Nasri, who promptly gave Pepe Reina his first anxious moment with a dipping shot that the Liverpool keeper turned to safety.
As City finally showed signs of life, Micah Richards set up James Milner in the area but his shot was high and wide.
City gained momentum from their improvement and carried the attack to Liverpool after the restart. Martin Kelly's poor back pass almost let in Sergio Aguero but the striker was driven too wide by Reina.
Reina was in action again on the hour, blocking Richards' header from Nasri's corner, prompting a change from Dalglish as he introduced defender Jose Enrique for Downing.
City made a change of their own with 24 minutes left, sending on striker Edin Dzeko for Adam Johnson, who endured a frustrating night.
The Premier League leaders continued to monopolise possession but, with Jamie Carragher on as a central midfielder to bolster Liverpool's defensive resources, City never looked like breaking through.
City were furious at Johnson's late challenge on Lescott, which was not even deemed worthy of a free-kick by referee Lee Mason.
Mancini considered the challenge worse than the Kompany tackle on Nani that earned the City captain a red card in the 3-2 defeat to United and a four-match ban.