Daniel Sturridge and Ramires struck in extra time to send Chelsea into the quarter-finals of the Capital One Cup. Manchester United's young centre-half, Scott Wootton, had defended well for so long but his inexperience was eventually found out.
Wootton fouled Ramires with seconds of normal time remaining, gifting Eden Hazard the chance to make it 3-3 from the spot. The Belgian duly delivered. Then Wootton's poor header allowed Sturridge to run through and score in the first half of extra time, with Ramires rounding goalkeeper Ander Lindergaard to add gloss to the scoreline with a fifth.
This was a night of occasional off-field tension at the Bridge, with a pitch invader, a couple of fireworks and United fans teasing their hosts about their current issues with the referee, Mark Clattenburg.
On the day that Chelsea formally lodged a complaint with the FA, alleging that Clattenburg had made a remark of a racist nature to John Obi Mikel, the Nigerian began the game but was booked in the first half and was sensibly withdrawn at the break by Roberto Di Matteo.
Mikel had started the tie, partnering Oriol Romeu in the centre, in a stronger than expected Chelsea team. Suspensions had ruled out Fernando Torres, John Terry and Branislav Ivanovic yet there was still Petr Cech, Gary Cahill, David Luiz and Juan Mata in the line-up.
Nani had a free-kick held by Cech. Chelsea's keeper then saved from Danny Welbeck following good work by Ryan Giggs and Anderson, whose juggling skills to create a yard of space were a treat to behold.
United were threatening on the break but their first-half goals came from mistakes, initially and surprisingly from Cech after 22 minutes.
Cech stroked his goal-kick straight out to Romeu, always a dangerous move as United had been pressing hard, fast and high.
Anderson was swiftly on to Romeu, nicking the ball into the path of Giggs with the goal exposed. Cech hurriedly tried to scramble across, but Giggs was moving with clinical intent. One touch teed the ball up. Giggs then looked up to check how far Cech had managed to get back across. Not enough. Giggs' second touch with his left foot sent the ball arrowing between the despairing Cech and the keeper's right-hand upright.
Frustration briefly flowed through Chelsea. Their fans were furious that the referee, Lee Mason, cautioned Mikel and Romeu for fouls but not Rafael for bringing down Lucas Piazon, even Alexander Buttner for catching Moses for the Chelsea penalty after the half-hour mark. It was a clear penalty, swiftly dispatched by Luiz, although Lindegaard got close.
Chelsea fans were then treated to the bad side of Luiz, the lax side.
With four minutes remaining to half-time, the Brazilian lost the ball in midfield and United exploited such largesse.
His compatriot, Anderson, played a delightful ball through to release Hernandez, who placed his shot unerringly past Cech.
Chelsea were soon level early in the second half, following a spell of pressure. Mata had just released Sturridge, whose scampering journey towards goal was ended only by a superb tackled from Rafael.
Chelsea continued to press. From a Mata corner, Cahill rose powerfully and sent the ball flying goalwards. Rafael, standing inside the goal, cleared it but the assistant referee correctly signalled it had crossed the line. United simply shrugged off their frustration at losing the lead by scoring a wonderful third.
Hernandez was lurking around the box but eventually turned away and found Nani. Oft criticised for his final ball, Nani was magnificent here, moving in a blur through blue shirts, exchanging passes with Anderson before dinking the ball past Cech.
In a game that flowed between the boxes, Moses should have equalised from Eden Hazard's cross but headed over. Cesar Azpilicueta then wasted a marvellous Mata ball, heading well over. "Time to blame the referee," chanted the United fans as their Chelsea counterparts sighed.
The home supporters were then up in arms when Mata's cross hit Michael Keane's hand. With Hazard and Oscar on, Chelsea attacked in waves. Moses and Ryan Bertrand were stretching United but still they refused to yield.
Wootton blundered again eight minutes into extra time, his ill-considered attempt at a header back to Lindegaard allowing Sturridge the chance to run through and make it 4-3 to Chelsea.
Nani and Oscar then squared up, hardly a battle of the heavyweights, before a touch of controversy invaded proceedings. Michael Keane fouled Sturridge as he went through, bringing baying calls for his expulsion.
Even Branislav Ivanovic, sitting behind the Chelsea dug-out, was out of his seat, waving an imaginary card. From the free-kick, Luiz almost snapped the bar.