Liverpool 1, Aston Villa 3: Full Time Report
A taste of what was to follow came from Villa's first chance came when Davies met a Nicky Shorey cross with a strong header, but it went straight at Jose Reina.
Torres and Steven Gerrard both saw shots blocked in the six-yard box, before Young was booked after 12 minutes for halting a Dirk Kuyt run.
Then Gerrard struck a first-timer from 20-yards just over from Kuyt's touched pass.
But Liverpool's problems were beginning to mount in a midfield that they were unable to dominate.
Javier Mascherano and Lucas were both fortunate not to be cautioned for fouls on Petrov and Agbonlahor in quick succession.
Torres was also coming in for some rough treatment from Carlos Cuellar, two tackles from behind going unpunished by referee Martin Atkinson.
By now Nigel Reo-Coker and Steve Sidwell were successfully breaking up Gerrard's flow in midfield, and Villa were soon to take the lead.
It came after 33 minutes when Lucas gave away a needless free-kick in midfield. Young swung the set-piece towards the near post, and it was the unfortunate Lucas who rose to head the ball past Reina for an own-goal.
Liverpool's play was sloppy and far too much possession was being conceded with ill-directed passes.
Further calamity came after Reina was booked in first half injury time for kicking the ball away in annoyance when referee Atkinson awarded a disputed corner, Sidwell's shot looking to have clipped a defender.
And from that disputed corner Villa found themselves two up. Shorey's corner swung into the near post and was headed home by Davies.
The hosts have staged some amazing comebacks in this stadium over the years, and they were going to need another massive performance to salvage anything from this situation.
Villa defended with organisation and desire. Roe-Coker was booked for kicking the ball away, and Friedel produced a fine save from a Kuyt header.
Kuyt then saw another header hit a post from a Gerrard corner from the left.
But Villa were still showing great resilience, and breaking quickly to cause Liverpool all sorts of problems at the back, Reo-Coker being only inches away from a third with one sliding attempt.
Liverpool sent on Andriy Voronin for Lucas after 66 minutes, with Friedel producing another fine stop from a Gerrard drive soon after.
But after 72 minutes Liverpool finally gave themselves some hope when Emiliano Insua got down the left and rolled the ball into the six-yard box for Torres to score.
Two minutes later Liverpool were back in despair and Villa celebrating. Shorey's pass into the path of Reo-Coker saw the midfielder surge into the box only to be felled by Gerrard's desperate tackle.
It was a clear penalty and Young stepped up to restore Villa's two-goal lead.
Liverpool's frustration was obvious. Torres was booked for dissent when Young went down injured and asked for treatment. He was eventually replaced by Heskey.
Ryan Babel came on for Benayoun, Liverpool still coming forward. Friedel again made a fine save from a Torres flick, before Kuyt sent a close range effort wide of the far post.
The outstanding Friedel, against his former club, saved from Torres and Glen Johnson, with Skrtel booked in the dying minutes, but Villa held on for a famous victory.
