EDEN HAZARD and Ramires ruined Wayne Rooney's goalscoring return as Chelsea's stylish comeback earned an FA Cup replay neither side wanted.
Javier Hernandez and recalled Rooney struck top-class goals inside the first 13 minutes to confirm Manchester United's early control.
But, despite some more decent home chances, the Blues' fluent response offered hope of a second-half revival that they conjured impressively.
Hazard curved a 59th minute goal from nothing at the peak of the Blues'
revival. Then Ramires' left-foot finished off a precision break with the visitors' leveller eight minutes later.
The replay winners face Manchester City - but Chelsea boss Rafa Benitez declined to think of that semi-final cracker ahead of the replay.
He said: "We have to think about the first game and, afterwards, think about City. It will be tough, will be difficult, United are a great side." Yet Juan Mata was only denied a neat last-minute winner by United keeper David de Gea's fingertip save after the outstanding Chelsea playmaker had weaved to the fringe of the six-yard box.
And there was still time for Blues substitute Fernando Torres to go almost as close.
That just underlined how Benitez's clutch of replacements - despite derision from some travelling fans - had transformed the contest after the break.
Key man Mata admitted to being both proud of the Blues' display and disappointed with the result.He said: "We were playing in a stadium like Old Trafford and it was Man United, so it could be a good result.
"But in the second half we had so many chances to score. De Gea was good, saving some of them.He saved very well (from me), with a foot I think, and Oscar had so many chances.
"It's a day to be proud of the team. (United) scored two in the first minutes but we tried very hard and came back.
"We have a replay at home, we are strong at Stamford Bridge with our supporters, and we will try to get through." Man Utd: De Gea, Da Silva, Evans, Ferdinand, Evra, Carrick, Cleverley, Nani (Valencia 45), Kagawa (Welbeck 76), Rooney, Hernandez (van Persie 62). Subs Not Used: Amos,Anderson,Vidic,Young.
Goals: Hernandez 5,Rooney 11.
Chelsea: Cech, Azpilicueta, Luiz, Cahill, Cole, Ramires, Lampard (Mikel 52), Moses (Hazard 52), Mata, Oscar, Ba (Torres 77). Subs Not Used: Turnbull,Ivanovic,Terry,Bertrand.
Booked: Azpilicueta,Luiz,Hazard.
Goals: Hazard 59,Ramires 68.
Ref: Howard Webb (S Yorkshire).