With the Blues in danger of crashing out of Europe’s premier club competition before Christmas for the first time, Andre Villas-Boas abandoned the cavalier tactics that have been the hallmark of his reign to date.
The counter-attacking approach paid off spectacularly as Chelsea emerged from the brink of elimination to top the group thanks to Drogba’s brace either side of a goal from Ramires and Bayer Leverkusen’s failure to win at Genk.
That meant the Blues avoid a last-16 clash against the likes of Barcelona, Real Madrid, Bayern Munich and Inter Milan.
Seemingly backed to the hilt by billionaire owner Roman Abramovich, Villas-Boas flexed his muscles this week by banishing Nicolas Anelka and Alex from his first-team squad, and he was ruthless again on Tuesday night by axing Frank Lampard from his starting XI.
It was not the first time Lampard had been left out this season but the midfielder’s omission was arguably the most significant of his entire Chelsea career.
It demonstrated the 33-year-old was no longer guaranteed to start the big games – and it did not get any bigger than this.
Chelsea went into the game in the unfamiliar position of needing to win to be certain of avoiding the humiliation of dropping into the Europa League, having thrown away victory in three of their previous five games.
So the fastest goal they had ever scored in the Champions League could hardly have been better timed as Drogba put them ahead inside three minutes.
Daniel Sturridge picked out Juan Mata at the far post and the Spaniard squared to Drogba, who was given an age to fire left-footed beyond Diego Alves.
The sense of relief around Stamford Bridge was palpable but the mood quickly changed as Valencia, who still only needed one goal to knock Chelsea out, assumed complete control.
They twice went close to levelling inside the opening 10 minutes when Jordi Alba crashed a shot against the outside of the post and Petr Cech clawed David Albelda’s blockbuster away from the top corner.
Villas-Boas had promised Chelsea would go on the attack but they were playing with 11 men behind the ball at times as the Valencia onslaught continued.
Villas-Boas’ much-maligned defence was hardly looking secure but the pressure was suddenly relieved midway through the half when Valencia produced an absolute howler in their own rearguard.
Drogba’s pass looked too heavy for Ramires but the Brazilian brushed off the feeblest of challenges from Victor Ruiz before slotting underneath the stranded Alves.
The home side were now playing almost exclusively on the break, defending as deep as they ever had done under Villas-Boas, but they almost added a third when another surge saw Alves keep out Sturridge’s near-post finish.
The pattern continued after half-time, with Sturridge going close again on the counter before Valencia brought on Aritz Aduriz and changed from a 4-5-1 to a 4-4-2 formation.
A goal for the Spaniards was all that was needed to set nerves jangling again and Cech got a crucial punch to Tino Costa’s crossed free-kick before springing sideways to repel Sofiane Feghouli’s goalbound drive.
Villas-Boas responded by sending on John Obi Mikel for Ramires, which yielded a mixed response from the home fans.
Drogba should have made the game safe with 18 minutes remaining when he left Adil Rami in a heap bursting onto Sturridge’s ball over the top but dragged wide with the goal at his mercy.
The striker made amends four minutes later after being slid in by Mata and poking the ball past Alves with the outside of his right foot for his fourth goal in the last four games.
Cech produced another excellent reaction save to keep out Aduriz’s header after Fernando Torres replaced Drogba.
With the final whistle looming, two of Chelsea’s fans got carried away and invaded the pitch but they could be forgiven after what they had been put through this season.