Roberto Di Matteo and Sir Alex Ferguson had to be separated as Manchester United ended their ten-year wait for an English Premier League win at Chelsea in controversial fashion
The Blues finished with nine men and were beaten by a late winner as United made up for all the bad luck they had suffered at Stamford Bridge in one fell swoop to cut their opponents' lead at the top of the league to one point.
Referee Mark Clattenburg sent off Fernando Torres for diving after Chelsea had fought back from a David Luiz own-goal and Robin van Persie's ninth of the season to equalise through Juan Mata and Ramires.
Branislav Ivanovic saw red five minutes before Torres, whose second yellow card prompted furious exchanges between the rival managers, and that was before Javier Chicharito Hernandez's winner, which had home fans screaming for an offside call.
United were celebrating a two-goal lead after 12 minutes as they became the latest top side to ruthlessly expose Chelsea's shortcomings. The opener took less than four minutes, the Blues losing possession and Van Persie crashing a shot against the post, the ball rebounding in off the luckless Luiz.
Ivanovic was fortunate to escape a booking for clattering into Young before United struck again, Ferdinand this time the architect. The veteran ambled out of defence and found Rafael, who fed Antonio Valencia, with the winger's low cross instantly swept home by Van Persie.
It was a goal of embarrassing ease against a Chelsea side Di Matteo had warned about the way they were starting games, but the European champions finally woke up midway through the half when Michael Carrick chopped down Ramires.
Luiz's brutal free-kick was saved by David De Gea's legs, the Spaniard deviating from the goalkeeping coaching manual again to keep out Gary Cahill's header.
Torres was having another shocker, but his failure to react to a corner missed by everyone else was forgivable and his header was only just kept out by a brilliant De Gea save. The goalkeeper could do nothing, though, when Wayne Rooney needlessly upended Eden Hazard a minute from half-time - earning a booking - and Mata stepped up to curl a sumptuous free-kick into the corner.
Mata would have equalised moments later had De Gea not made amends for a horrendous clearance before Torres earned his first booking for a foul on Tom Cleverley.
Mata leads Chelsea revival
But Chelsea needed only seven minutes of the second half to deservedly level as Mata took the game by the scruff of the neck. After scuffing a right-foot shot, he showed sublime control to keep Oscar's ball in play, allowing the Brazilian to cross again for Ramires to head home.
Hazard had two more sniffs before United got a grip. And they were given a golden opportunity to snatch all three points as disaster struck for Chelsea when Ivanovic and Torres were both sent off in the space of five minutes.
Ivanovic could have no complaints, the right-back seeing red for bringing down Young, who had been played clean through by Van Persie. Rooney fired the resultant free-kick just over before United replaced the ineffective Cleverley with Hernandez and Chelsea sent on Cesar Azpilicueta for Oscar.
They were about to bring on Daniel Sturridge for Torres, but the striker joined Ivanovic in the dressing room when he was shown a second yellow for diving, TV replays seeming to indicate he'd been caught by Evans. Torres was furious, trudging off and having words with the fourth official, who was then forced to keep Di Matteo and Ferguson apart on the touchline.
Ryan Bertrand joined the fray instead of Sturridge, but Chelsea faced an impossible task with nine men and Hernandez snatched what proved the winner 15 minutes from time from an offside position.
Petr Cech brilliantly tipped Van Persie's shot onto the post, but Rafael followed up and Hernandez turned the ball home. Mikel was booked for his protest, Sturridge entered the fray and Valencia also saw yellow as well as wasting a chance to kill the contest.