John Terry capped an unforgettable night of Champions League drama at Stamford Bridge by heading Chelsea into the quarter-finals as Jose Mourinho's side showed their indestructible character.

Chelsea, who were 2-1 down from the first leg, had been in serious danger of naively throwing away a seemingly assured win despite having struck three times in the opening 19 minutes of the rematch.

Even though the Blues led 4-2 on aggregate at one stage, Ronaldinho inspired Barcelona back into the game with a penalty and then a magical strike which took the Spanish side ahead on away goals before half-time.

However, after a second half of unrelenting thrills and spills, with Petr Cech performing heroics to hold Barcelona at bay and luck on their side, the inspirational Terry had the final say.

The Chelsea skipper's fourth goal in the competition this season came with just 14 minutes left, but it was enough to keep his side's treble dreams very much alive.

Mourinho flung himself into an ecstatic sea of players at the final whistle, while Barcelona were shepherded down the tunnel amid angry recriminations, scuffles and, seemingly, even spitting.

So much for being boring. Having been accused of negative tactics in the Nou Camp, Mourinho had bravely fielded Mateja Kezman just ahead of Gudjohnsen after two goals in his past two games.

Amid an aggressive start by the home side, Kezman made an immediate impact, surging down the right flank after Lampard had won possession before producing an inviting cross for his strike partner.

Gudjohnsen's first touch took him past Gerard, before then lunging forwards to power his shot past goalkeeper Victor Valdes with just eight minutes gone.

That was, in itself, enough to take Chelsea through but their tails were up and Lampard shot over the bar on the turn from just eight yards out.

No matter. At this stage, Chelsea were rampantly pouring forward and when Joe Cole's shot was deflected, Valdes could only parry the ball and Lampard was onto it in a flash to finish.

"Boring, boring Chelsea" rang out ironically around Stamford Bridge, but the home side were not finished there.

Next it was Cole producing the midfield inspiration, driving a through-ball for Duff to scamper onto and roll underneath the body of the stranded Valdes.

That should have been game over. The time to regroup, refocus and recharge the batteries. Instead, Chelsea continued to attack and quickly paid the price.

Not even two warning signals, when Cech denied Samuel Eto'o at full stretch and Ronaldinho directed a header just inches wide were enough.

For when Paulo Ferreira, with his back to the ball, unnecessarily handled, Ronaldinho converted the ensuing penalty and the tie was transformed.

Now Barcelona only needed one goal to go through and even though Cech again performed acrobatics to deny Deco, Ronaldinho duly obliged.

Not that there seemed much danger when the Brazilian was confronted by an imposing wall of defenders on the edge of the penalty area.

But with a minimal back-lift, he still conjured a moment of pure inspiration as he crafted a shot that curled into the far corner, leaving Cech motionless.

Eto'o also skimmed a shot over the bar from Ronaldinho's inspired through-ball, but Chelsea rallied and Cole struck the post, with Duff just failing to convert the rebound as he stretched.

And that was all in the first half.

Ferreira was withdrawn soon after the restart after suffering a torrid time at Ronaldinho's hands, with Glen Johnson the next to be run ragged by the Brazilian.

However, Chelsea are made of sterner stuff these days and although they lacked shape, Terry and Lampard led the revival as the match continued to fizzle with excitement.

Lampard twice came close, but Cech just scrambled Juliano Belletti's long-range effort around the post and then produced an incredible save from Carlos Puyol.

Valdes, meanwhile, was also equal to a thunderbolt from Cole, while Lampard and Gudjohnsen both threatened.

However, Chelsea left themselves open to the counter-attack and when Cech tipped Andres Iniesta's shot onto the post, Eto'o should have punished Johnson's hesitation.

That was the escape they needed. For when Terry headed home Duff's corner, Barcelona's desperate pleas for an imagined flag from the linesman came to nothing.

Mourinho immediately introduced Tiago for Gudjohnsen and defender Robert Huth soon followed in a five-man amid a frantic final spell as Deco flashed an injury-time free-kick just wide.

Stamford Bridge nevertheless erupted at the final whistle. It had, indeed, been a truly incredible night.

Barcelona's recriminations began, with angry scenes as they left the pitch. But Chelsea's Champions League dream remained alive - and thrillingly so.

Teams:

Chelsea Cech, Paulo Ferreira (Johnson 51), Terry, Ricardo Carvalho, Gallas, Makelele, Cole, Lampard, Duff (Huth 85), Kezman, Gudjohnsen (Tiago 78).

Subs Not Used: Cudicini, Smertin, Geremi, Parker.

Booked: Paulo Ferreira, Kezman, Johnson.

Goals: Gudjohnsen 8, Lampard 17, Duff 19, Terry 76.

Barcelona Valdes, Belletti (Giuly 84), Puyol, Oleguer, Van Bronckhorst (Sylvinho 45), Deco, Gerard, Xavi, Ronaldinho, Eto'o, Iniesta (Maxi Lopez 85).

Subs Not Used: Jorquera, Fernando, Albertini, Damia.

Booked: Van Bronckhorst, Xavi.

Goals: Ronaldinho 27 pen, 38.

Att: 41,515

Ref: Pierluigi Collina (Italy).