Match ends, Chelsea 1, Stoke City 0.
Oscar's sublime free-kick was enough to end Stoke's interest in this season's FA Cup and earn Chelsea a fifth round trip to Manchester City.
The Blues, winners of the trophy four times in the last seven seasons, wasted a bundle of chances and hit the post twice in a one-sided cup tie.
But they only had Oscar's breathtaking 25-yard strike to show for their dominance and were forced to endure a nervy final few moments before securing the victory.
The Potters barely threatened but Stephen Ireland wasted a great chance before the break, smashing a shot into the side netting from close range.
Stoke's hopes of a cup shock had seemed slim and so it proved.
The visitors had won just two games since an impressive last-gasp 3-2 win, over Chelsea on 7 December, beating Aston Villa in the league and Championship leaders Leicester City in the last round of the Cup.
But six consecutive victories and 10 wins from 13 since that setback at the Britannia have taken Chelsea to within two points of the Premier League summit.
Chelsea's failure to make their first-half dominance count proved their undoing the last time the two sides met. They were once again guilty in front of goal but it did not matter.
Facing a side likely to stack up in defence and flood the midfield, it looked like just the sort of match when the guile and quality of Manchester United new boy Juan Mata would be most required.
But the Blues did not need their two-time player of the year, and once again it was the pace, direct running and trickery of Eden Hazard and Oscar that did the main damage.
With the giant figure of Nemanja Matic dominant in midfield on his (second) full debut, the hosts bossed possession and made full use of it.
Oscar scored a majestic 25-yard free-kick, curling the ball over the wall and into the far corner to win the game.
But it was Hazard who stood out with a breathtaking display. The Belgian tormented the Stoke defence from the first minute, sparking all that was good about a fine attacking display and earning bookings for Geoff Cameron and Marc Wilson.
Hazard and Chelsea started impressively. Samuel Eto'o shot narrowly wide inside two minutes and although Stoke could have easily have led when Peter Crouch sent a header off target soon after, it was a half dominated by the hosts.
Several promising Hazard-inspired breaks failed to lead to strikes on goal but, with the pressure mounting, Oscar put the Blues ahead - and they should have been out of sight by half-time.
Frank Lampard could not stretch out to divert the ball in from close range after a snaking run from Hazard and also shot over from 20 yards.
In between Oscar hit the post with a well-struck low cross-shot that led to Stoke's best chance of the game.
The Potters broke with good pace and worked the ball in to Ireland but he smashed a near-post shot just off target with Mark Schwarzer beaten.
However that opening provided brief respite for the visitors.
The second half started as the first ended, with Chelsea cracking the frame of the goal and Jose Mourinho doing plenty of head shaking at his side's failure to kill the game off.
A fierce strike by Andre Schurrle crashed against the post with Asmir Begovic beaten and Oscar almost added his second with a sweet first-time effort that curled just wide of the far post.
Stoke boss Mark Hughes changed tactics in the final 20 minutes, moving the ever-willing Jonathan Walters up front alongside Crouch.
The chances remained Chelsea's though. Lampard had a fizzing low shot well saved by Begovic and Eto'o inexplicably spooned an effort wide after a goalmouth melee, the striker getting his feet in a muddle five yards out with the goal gaping.
Begovic then made a brilliant diving stop to keep out a thunderous David Luiz free-kick, but ultimately Chelsea did not need the luxury of a second goal.
Check out the action from today's FA Cup ties on the BBC Sport Facebook page.
- 4David Luiz
- 14SchürrleSubstituted forSantos do Nascimentoat 70'minutes
- 11OscarSubstituted forWillianat 81'minutes
- 17E Hazard
- 29Eto'oSubstituted forBaat 85'minutes
- 7Santos do Nascimento
- 20CameronBooked at 32mins
- 12WilsonBooked at 45mins
- 3PietersBooked at 83minsSubstituted forMuniesaat 85'minutes
- 8PalaciosSubstituted forAssaidiat 72'minutes
- 10ArnautovicSubstituted forAdamat 83'minutes
- Chris Foy
- Shots on Target
Second Half ends, Chelsea 1, Stoke City 0.
Attempt blocked. Charlie Adam (Stoke City) left footed shot from outside the box is blocked. Assisted by Stephen Ireland.
Offside, Chelsea. David Luiz tries a through ball, but Demba Ba is caught offside.
Ramires (Chelsea) wins a free kick in the defensive half.
Foul by Peter Crouch (Stoke City).
Delay over. They are ready to continue.
Delay in match Ryan Shawcross (Stoke City) because of an injury.
Attempt blocked. Willian (Chelsea) right footed shot from the left side of the box is blocked. Assisted by Ashley Cole.
Substitution, Stoke City. Marc Muniesa replaces Erik Pieters.
Substitution, Chelsea. Demba Ba replaces Samuel Eto'o.
Corner, Chelsea. Conceded by Asmir Begovic.
Attempt saved. David Luiz (Chelsea) right footed shot from outside the box is saved in the top left corner.
Substitution, Stoke City. Charlie Adam replaces Marko Arnautovic.
Erik Pieters (Stoke City) is shown the yellow card for a bad foul.
Ramires (Chelsea) wins a free kick in the attacking half.
Foul by Erik Pieters (Stoke City).
Substitution, Chelsea. Willian replaces Oscar.
Foul by Branislav Ivanovic (Chelsea).
Oussama Assaidi (Stoke City) wins a free kick on the left wing.