Dirk Kuyt came off the bench to score the winning goal as Liverpool knocked North-West rivals Manchester United out of the FA Cup this afternoon.
Hosts Liverpool created the opening chance of the match but David de Gea was on hand to turn Maxi Rodriguez's effort wide of goal.
United winger Antonio Valencia went even closer in the 17th minute, only for his long-range effort to strike the outside of the post.
The deadlock was eventually broken in the 20th minute, with De Gea at fault. The Spanish goalkeeper got nowhere near a Steven Gerrard corner and Daniel Agger capitalised to head into an empty net.
However, United drew themselves level before the break. Full-back Rafael beat Jose Enrique down the right and crossed for Park Ji-Sung, who shot first time past Pepe Reina at the near post in the 39th minute.
Neither goalkeeper was called into any telling action after the restart as the tie looked to be heading for a replay.
However, with just two minutes of normal time remaining, Kuyt ghosted past Patrice Evra before shooting low past De Gea to win the match.
It could have been three for the hosts in stoppage time, but Andy Carroll's header struck the crossbar, while Kuyt failed to convert the rebound.
It didn't prove costly for the home team though, who held out to secure their progress into round five.
