Liverpool have a long-standing habit of upping their game against the bigger clubs, and they started the brighter of the two sides, and almost broke the deadlock soon after kick-off after Luis Suarez spun to release Glen Johnson, but the England full-back's toe-poke was wide of the post.
Chelsea soon grew into the game however, and as usual, when they could get their trio of Oscar, Juan Mata and Eden Hazard combining, they looked incredibly dangerous. The three combined to produce a fine chance for Oscar, but he wasted the chance with a tame effort straight at Pepe Reina.
Yet Liverpool's energetic midfield was mostly doing a fine job of keeping the three from playing their best football, although they almost didn't require them as Ramires elected to shoot from 30 yards, a fine effort that required Pepe Reina to be alert to keep it out. Shortly afterwards, it was a corner that gave the visitors their breakthrough - Oscar, of all people, with a glancing near-post header after eluding the inadequate attention of Jamie Carragher.
Another long-range effort, and another set-piece almost put Chelsea two up - David Luiz's free-kick from fully 35 yards was well struck, but Reina should have had it easily, only to fumble it but managed to regather the ball just before it trickled over the line. Aside from a fierce Suarez effort that Petr Cech managed to keep out, it proved to be the last chance of the half.
Daniel Sturridge replaced the ineffective Philippe Coutinho at half-time, and the former Chelsea man immediately looked dangerous, first playing in Steven Gerrard only to see him denied by Petr Cech, and then letting fly with a thunderous effort from 30 yards that clattered off the post.
It was no surprise, then, to see the source of Liverpool's equaliser. Suarez was the creator, as he floated in a perfect cross, and Sturridge took just seven minutes to register his goal, side-footing in past Cech and levelling the scores.
Suarez, however, would soon undo Liverpool's hard work - the Uruguayan needlessly handballed from a Chelsea corner straight afterwards and a penalty was duly awarded. Pepe Reina attempted his best delaying tactics for Eden Hazard, but the Belgian sent him the wrong way from the penalty spot to restore Chelsea's advantage.
Liverpool thought they should have had a penalty afterwards as he was leapt on by David Luiz, but the referee correctly judged the foul to have taken place just outside the area. It was still a good opportunity for Liverpool, but Suarez dragged the free-kick just wide of the post.
The game was then marred by an utterly bizarre incident as, during a tussle with Branislav Ivanovic, Suarez bit the midfielder on the arm, a strange repeat of an incident where he previously had a taste of Otman Bakkal while playing for Ajax - for which he was suspended for seven games. It wasn't noticed by the referee, so some further action from the FA is surely due.
Jonjo Shelvey entered the fray as Liverpool sought an equaliser, but he was guilty of the worst miss of the game, Henderson squaring the ball to him with the goal gaping, but the former Charlton midfielder could only hit the side-netting with his effort.
With time running out, Liverpool were pushing hard for a goal - the source was predictable, dramatic, typical - the player who had no right to be on the pitch, Luis Suarez, found the net in the very last minute from Daniel Sturridge's cross, getting away from Branislav Ivanovic to head past Cech. A remarkable result, but the fallout from this game will go on and on.