Chelsea 1 Stoke City 0
Oscar’s brilliant 30-yard free-kick took Chelsea into the FA Cup fifth round.
The Brazilian, who was outstanding throughout, superbly swept the ball over the Stoke wall and into the far corner on 27 minutes.
He later hit the woodwork, as did Andre Schurrle, as Mark Hughes’ side escaped a thrashing despite being totally outplayed.
Chelsea, who have been drawn to face Manchester City at the Etihad Stadium for a place in the quarter-finals, were well on top before the opener and Samuel Eto’o almost put them ahead in only the third minute.
Eto’o, a surprise choice given that boss Jose Mourinho had hinted that Demba Ba would play, turned cleverly and sent a low shot inches wide of the post.
At the other end, Peter Crouch headed wide after holding off David Luiz to meet Jon Walters’ left-wing cross.
Chelsea kept pressing after going ahead – an unmarked Branislav Ivanovic could not quite jump high enough to get his head to a free-kick from Frank Lampard, who was then just unable to connect with Eden Hazard’s cross.
And moments after Stephen Ireland almost equalised on the counter-attack, shooting into the side netting from nine yards, Oscar fired against the post.
Oscar continued to turn on the style after the break, running at the heart of the Potters defence and picking out Schurrle, whose drive struck the angle of post and bar.
Oscar then belted wide following a lovely passing move and had a powerful effort held by Asmir Begovic, who did well to keep out a low shot from Lampard and push over Luiz’s thumping free-kick.
Hazard was also on top form and one of several jinking runs down the left by the Belgian resulted in a goalmouth scramble that ended with Eto’o poking wide from four yards out.
Chelsea: Schwarzer; Ivanovic, Luiz, Cahill, Cole; Matic, Lampard; Schurrle (Ramires 69), Oscar (Willian 80), Hazard; Eto’o (Ba 84).
Subs not used: Cech, Azpilicueta, Terry, Mikel.