Liverpool's recent slump continued as they were beaten by Charlton to go down to a third defeat in four league games.
Darren Bent's pace caused Liverpool a lot of problems
A controversial penalty decision allowed Charlton to take the lead with striker Darren Bent slotting home.
Luke Young's angled drive extended the home lead to further shock a Reds side lacking a cutting edge.
Darren Bent and namesake Marcus each hit the woodwork while a well-struck Fernando Morientes strike was saved in Liverpool's best chance of the game.
Liverpool were without influential captain Steven Gerrard but dominated possession in the early stages as they probed for an opening.
But the visitors did little to quell the doubters who say they lack an end product as strikers Morientes and Peter Crouch each looked unsure in front of goal.
Spaniard Morientes flicked a near post shot straight at Charlton keeper Thomas Myhre while Crouch's control let him down when in space at the far post.
Young's goal came at a crucial time for Charlton
The match was in danger of petering out before Charlton were awarded a penalty when Dudek was punished for apparently clipping Darren Bent as he raced onto a Radostin Kishishev ball.
Liverpool felt the decision was harsh while the Addicks thought Dudek should have been sent-off.
But Darren Bent made light of the controversy by slotting home for his 15th goal of the season.
It got worse for Liverpool on the stroke of half-time when Alexei Smertin's low cross was only half-cleared and right-back Young burst into the Reds box to strike a shot through Dudek's legs.
The visitors left themselves exposed at the back as they pressed for a goal and a Darren Bent cross was just too high for unmarked striker partner Marcus Bent as a resolute Charlton looked to take advantage.
Darren Bent rattled the crossbar with a 20-yard half-volley before he again set up Marcus Bent to sidefoot against the post.
Liverpool's pressure finally created a clearcut chance and, even though Morientes struck a true shot, keeper Myhre was equal to the shot.
The defeat was Liverpool's ninth successive loss in London as they suffered a blow in their attempts to catch Manchester United in second.
Charlton boss Alan Curbishley:
"We got lucky with the penalty," he said. "Darren was going in there full throttle. I don't think he's dived.
"The ref's given a penalty but you can count on one hand the amount we have had in the last five years."
"We got a bit fortunate with that but we were not fortunate after that as we gave as good as we got."
Liverpool manager Rafael Benitez:
"It wasn't a penalty.
"The defeat is difficult to explain.
"We need to learn from our mistakes as soon as possible. It wasn't a penalty but we lost the ball when we were controlling the game."
Charlton: Myhre, Young, Perry, Hreidarsson, Spector, Hughes, Kishishev, Smertin (El Karkouri 83), Thomas (Ambrose 79), Marcus Bent, Darren Bent.
Subs Not Used: Andersen, Euell, Bothroyd.
Booked: Thomas, Perry.
Goals: Darren Bent 42 pen, Young 45.
Liverpool: Dudek, Finnan, Hyypia (Riise 70), Carragher, Traore, Cisse (Kromkamp 78), Sissoko, Alonso, Kewell, Morientes, Crouch (Fowler 60).
Subs Not Used: Carson, Hamann.
Booked: Dudek, Carragher.
Ref: A Marriner (W Midlands).