Manchester United boss Jose Mourinho told Chelsea supporters "Judas is number one" after Antonio Conte guided the Blues into the FA Cup semi-finals.
N'Golo Kante's strike settled a bad-tempered contest 1-0 to set up a FA Cup semi-final with Tottenham for Conte's Premier League leaders, who could yet claim a double in the Italian's first season in charge.
Ander Herrera was sent off for two bookable offences and United players surrounded referee Michael Oliver, while Marcos Rojo appeared to tread on Eden Hazard. The Football Association may scrutinise those incidents and retrospective action could follow.
Mourinho, Chelsea's most successful manager, pointed to himself, then the pitch and signalled with three fingers - for the number of Premier League titles he won in two spells - after being subjected to abuse from a section of fans behind the visiting dugout.
One section of supporters chanted "F*** off Mourinho", "It's all your fault" - a reference to Chelsea's implosion last season - "You're not special any more" and "Judas".
"They can call me what they want," Mourinho told the post-match media conference.
"Until the moment they have a manager that wins four Premier Leagues for them, I'm the number one. Judas is number one."
Mourinho was sacked by Chelsea for a second time in December 2015, seven months after his third title success.
He again bemoaned the fixture schedule which saw the quarter-final tie take place between legs of United's Europa League last-16 tie with FC Rostov.
But he insisted Chelsea's absence from European football was not his responsibility as when he was axed, with the Blues perilously close to the relegation zone, they were still in the Champions League under interim boss Guus Hiddink.
He added: "It's not my fault. It's the fault of the ones that stayed here and didn't win the Champions League."
One honour which eluded Mourinho at Chelsea was the Premier League-FA Cup double which remains a possibility for Conte.
The Italian refused to be cowed by his predecessor and fourth official Mike Jones was required to separate the pair during a frank exchange. They did not shake hands on the pitch after the final whistle, but later did so in the tunnel.
Conte said: "What happened on the outside for me is only (a) circus."
Conte was incensed as United appeared to target Hazard.
"For Hazard, (for) 20, 25 minutes it was impossible to play football, because he received only kicks," Conte said.
"A tactic to play and go to kick an opponent? It's not football for me.
"The referee must protect these type of players. When they go out with a bad injury...
"It's very dangerous to receive a kick from the back."
Mourinho's comments on Oliver's performance were laced with sarcasm.
Mourinho told the BBC: "Mr Michael Oliver - a referee with fantastic potential. Manchester United were a bit unlucky. In four matches, three penalties and one red card in such an early moment of the game."
It was Mourinho's first FA Cup quarter-final loss as Chelsea won a club record 13th successive home game to progress to Wembley.
Chelsea beat Tottenham in December, but Spurs ended their 13-match Premier League winning streak at White Hart Lane on January 4.
"We start with one win for us and one win for them," Conte said.
"For sure it'll be an interesting game."
Manchester City and Arsenal meet in the other semi-final.
Source: PA
