A fortnight of worry forgotten after three minutes of decisive action.

Andre Villas-Boas might have sacrificed his ideals but his reward was a place in the knockout phase.

With the Stamford Bridge club in danger of exiting out of Europe's premier club competition before Christmas for the first time, the Portuguese coach abandoned the cavalier tactics that have been the hallmark of his reign in what was the club's final Group E game against Valencia. The counter-attacking approach paid off spectacularly as Chelsea scored inside the first 180 seconds to emerge from the brink of elimination to top the group.

A brace from Didier Drogba, a goal from Ramires and Bayer Leverkusen's failure to win at Genk even meant Chelsea avoided a last-16 clash with the likes of Barcelona, Real Madrid, Bayern Munich and Inter Milan, although they would gladly have taken that ahead of a game Villas-Boas had repeatedly billed as "life or death".

"Guess what? We finished top of the group against all odds," he said. "Our strategy was always to keep our line of defence close to our goal.

"The Premiership games - in our last four games we have had three clean sheets so our defence isn't that bad. I think the players have given everyone a slap in the face today. What matters is that Chelsea finished top of the group. We qualified in first and we await the draw to see how far we can go."

The 34-year-old had refused to countenance the prospect of failure, something he was nevertheless adamant would not cost him his job. 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 by dropping Frank Lampard from his starting XI. It was not the first time the England midfielder had been left out this season but Lampard'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 really did not get any bigger than this.

Chelsea needed 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 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' maligned defence was hardly looking secure but the pressure was 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 Alves.

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 but 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.