Chelsea win 5-4 on agg
John Terry's header sent Chelsea into the last eight of the Champions League after a classic clash with Barcelona.
Chelsea raced into a three-goal lead in 19 minutes, with Eidur Gudjohnsen, Frank Lampard and Damien Duff on target for Jose Mourinho's side.
But Barca pulled two goals back before half-time, Ronaldinho scoring from the spot after Paolo Ferreira handled.
Ronaldinho then scored a stunning second, but Terry headed home after 75 minutes to send Chelsea through.
After the acrimony surrounding the first leg, this clash also ended in controversy with Barcelona coach Frank Rijkaard having to be restrained as a fracas erupted near the tunnel.
Chelsea made the sort of start that was beyond even their wildest dreams - scoring three times inside the first 20 minutes.
They were in front after seven minutes, Mateja Kezman's brilliant pass releasing Gudjohnsen, who turned Juliano Belletti and slammed home an emphatic finish.
Lampard should have doubled Chelsea's advantage when he shot wildly over from close range, but made no mistake when presented with another opportunity after 16 minutes.
Joe Cole's deflected shot was brilliantly saved by Victor Valdes, but Lampard was perfectly placed to turn home Chelsea's second.
And two minutes later Chelsea were in dreamland, Duff racing on to Cole's pass to beat Valdes on the run.
But Barcelona's attacking brilliance cast a shadow over the mood of celebration inside Stamford Bridge - and they were back in charge of the tie before half-time.
Samuel Eto'o had fired narrowly over the top and Ronaldinho headed inches wide, but Chelsea failed to heed the warning signals.
Barcelona pulled a goal back after 25 minutes when referee Pierluigi Collina ruled that Paulo Ferreira had handled.
Ronaldinho tucked away the penalty - then produced a moment of dazzling brilliance seven minutes before the interval to score Barcelona's second and leave Chelsea needing to score a fourth.
There seemed no danger when the Brazilian took control 20 yards out, but with a trademark shimmy and no back-lift, he flashed a shot past a stunned Petr Cech.
As the players left the field at half-time, there was the unusual sight of Ronaldinho swapping shirts with Ferreira.
Barcelona started the second half with renewed confidence, and Cech had to save low from Belletti before producing a brilliant low save from Carles Puyol's header.
Chelsea had a massive escape with 18 minutes left, Cech somehow turning Andres Iniesta's shot on to the post, with the normally lethal Eto'o firing over from close range.
And Chelsea took advantage to go back in front with 15 minutes left, Terry powering Duff's corner past Valdes, who claimed he had been fouled by Ricardo Carvalho.
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.
Ref: Pierluigi Collina (Italy).