Chelsea's Michael Ballack grabbed an extra-time winner against Blackburn to set up an FA Cup final with Manchester United at Wembley on 19 May.
A tame Rovers had fallen behind when Frank Lampard raced on to a Ballack pass and angled in a shot.
But Blackburn produced a rousing fightback and Jason Roberts glanced in a shot before an unmarked Morten Gamst Pedersen headed wide from 10 yards.
The gripping tie went into extra time and Ballack slotted in on 109 minutes.
Chelsea had bided their time at the start of the game as they efficiently and comfortably contained Rovers, while searching for a breakthrough - which came in ruthless style after 16 minutes.
Keeper Petr Cech's long goal-kick found striker Didier Drogba and he used his strength to hold off towering centre-back Christopher Samba.
606: DEBATE
Drogba laid off the ball for Ballack to slide a pass into the run of Lampard, who skipped over a Ryan Nelsen challenge before sending an unerring finish across goal into the far corner.
Blackburn were having their game strangled out of them by Chelsea as the occasion seemed to send them into their shell.
But the Ewood Park side finally showed some signs of fight just before the break when David Dunn had a 20-yard strike saved by Cech.
Samba should have headed in the resultant corner only to see his effort go agonisingly over from eight yards.
Chelsea had a great chance to add a second shortly after the interval when they dubiously beat the offside trap.
Drogba broke through on goal before squaring the ball to an unmarked Shevchenko, who comically got his feet tangled up and fluffed his shot as he tried to sidefoot the ball in.
But Blackburn were a more forceful and forward thinking side in the second half as they finally shook off the shackles to give Chelsea a fright.
Roberts turned and rifled in an angled shot, which was well-saved by Cech at his near post.
Pedersen hit the post with a far-post header from a deep David Bentley corner before Blackburn's efforts were rewarded with an equaliser.
Roberts diverted the ball past a despairing Cech by deflecting a shot home from 10 yards.
Norwegian Pedersen had a free header after 82 minutes and looked set to give Rovers the lead only to put the chance inches wide.
Chelsea skipper John Terry then almost scored an own goal but had Cech to thank for saving his blushes as the keeper tipped the ball away at full stretch and the game went into extra time.
The Blues mounted the greater pressure and Ballack grabbed the winner after before a Michael Essien shot struck the crossbar late on.
Chelsea have already won the Carling Cup and this win keeps alive their Quadruple challenge as they are still in the hunt for the FA Cup, Premiership and Champions League.
Blackburn: Friedel, Emerton, Samba, Nelsen, Warnock, Bentley (Derbyshire 114), Dunn (Peter 106), Mokoena, Pedersen, Roberts, McCarthy.
Subs Not Used: Enckelman, Kerimoglu, Henchoz.
Booked: Emerton, Mokoena, Pedersen, Warnock.
Goals: Roberts 64.
Chelsea: Cech, Essien, Carvalho, Terry, Ashley Cole, Ballack, Makelele (Mikel 81), Lampard, Shevchenko (Kalou 63), Drogba, Joe Cole (Wright-Phillips 97).
Subs Not Used: Cudicini, Boulahrouz.
Booked: Mikel, Ballack.
Goals: Lampard 16, Ballack 109.
Att: 50,559
Ref: A Wiley (Staffordshire).