By the time Florent Malouda got the goal his fabulous performance deserved, Arsenal's supporters were already streaming for the exits, finished off for another season after finally losing the faith.
They were beaten by a team assembled for magic money, Arsene Wenger's latest barb at their big-spending neighbours after Chelsea handed out the mother of all beatings in Arsenal's backyard.
Gone backwards? More like gone at all levels.
Blues brothers: The Chelsea players celebrate Alex's goal
Key battles were not lost, they never even started. Mikael Silvestre versus Didier Drogba? No contest. Cesc Fabregas versus Frank Lampard? Forget it. Robin van Persie versus John Terry? An embarrassment.
It was a humbling experience for Wenger and his team, five days since Manchester United marched on to their territory and trampled all over them in the Champions League semi-final second leg.
Once Alex scored with a header in the 29th minute, they were done for, the shattered confidence draining the life out of their tired little limbs, barely able to string a pass together as Nicolas Anelka, an own goal by Kolo Toure and Malouda's 86th-minute strike saw them off.
They have not lost this badly in a home league game since 1977, when an emerging Ipswich side turned over Terry Neill's team at Highbury, crashing four past the Gunners as the glory years began under Bobby Robson.
Judging by events of the past five days, Arsenal's golden era has also gone, consigned to the time capsule that was buried under the main entrance when Arsenal made the �350million move to the Emirates in August 2006.
They occupy fourth position in the Barclays Premier League this morning, where they will remain until the final ball of the season is kicked against Stoke City on May 24, readying themselves for what is becoming an annual date with the Champions League qualifiers.
Match Facts
After this they need a summer to recover, to recharge the batteries and remind themselves that playing for Arsenal remains a great privilege. Their supporters deserve better, certainly better than this.
For 25 minutes they gave it a go, with Theo Walcott the most threatening Arsenal player, bounding his way past Chelsea's defenders and even poking his England team-mate Ashley Cole in the eye, much to the delight of the home support.
With a new 50,000-a-week contract in the post, he needed to show more composure in the opening minute, blasting his effort over Petr Cech's crossbar when Robin van Persie put him through.
So far so good as Arsenal peppered Cech's goal, with Abou Diaby sending another effort wide and Walcott steering an inviting chance to the right of the post. It appeared to be game on until Fabregas clipped Drogba's heels, earning an inevitable booking after motioning to referee Phil Dowd that the most unpopular striker in the history of English football had taken yet another dive.
From Drogba's subtle free-kick, Chelsea took the lead when Alex rose above the pathetic challenge of Silvestre to plant an excellent header beyond the reach of Lukasz Fabianski in the 29th minute.
Arsenal looked for a leader, someone who could drag them back into the game but Chelsea, inspired by the mazy dribbles and the ghosting runs of Malouda, were unstoppable.
Anelka scored their second just before half-time. It was too easy for the former Arsenal striker as he set himself up on the edge of the penalty area, fizzing a shot with the outside of his toe which spun away from Fabianski and into his bottom left corner.
Stretch too far: Arsenal keeper Fabianski can't get near Anelka's swerving shot
Chelsea's supporters, still hurting from the perceived injustice against Barcelona on Wednesday evening, lapped it up, reminding the opposition-of last month's mismatch at Wembley when they met in the FA Cup semi-final.
It got to Arsenal's players, notably Toure when he sent Cole's cross at the start of the second half beyond the stranded figure of Fabianski, a pitiful sight for this once great defender.
The believers, the survivors still in the stands, were given hope when Nicklas Bendtner's header in the 70th minute beat Cech, a well-taken effort which met with the approval of Arsenal's dwindling support.
Moments later their hopes of a comeback were destroyed when Anelka's angled effort rebounded off the post and Malouda restored Chelsea's three-goal advantage.
That was the signal for Arsenal's supporters to desert the stadium, turning their backs on the team as Chelsea's interim manager Guus Hiddink showed a playful side to his character by blowing kisses at them as they left.
After this, it might as well have been the kiss of death.