N'Golo Kante sent Chelsea into an FA Cup semifinal meeting with Tottenham by ending Manchester United's title defence on Monday, sealing a 1-0 victory after Man U's Ander Herrera was dismissed on a fiery night at Stamford Bridge.
Herrera was booked twice for fouling Chelsea winger Eden Hazard, leaving United a man down from the 35th minute while already trying to cope without suspended top-scorer Zlatan Ibrahimovic.
Kante broke the deadlock five minutes into the second half after France teammate Paul Pogba failed to close him down before unleashing a shot from 20 yards (metres) that beat goalkeeper David De Gea.
It was only the second goal for the midfield enforcer since joining Chelsea last year as a Premier League champion from Leicester. The other also came in the league against United, which hasn't won at Chelsea in five years.
"He's such a humble guy who works hard," Chelsea defender Gary Cahill said.
Former club Chelsea, the runway Premier League leader, remains on course to complete Antonio Conte's first year with a double. If Chelsea can get past London rival Tottenham in the semifinal, it will play either Manchester City or Arsenal.
But Jose Mourinho is left with only one route to silverware in his first season in charge of United in the Europa League.
It was a typically combustible return to Stamford Bridge for Mourinho. Adding to the theatrics, smoke was pumped across the field. Mourinho's achievements here across two spells have also been obscured.
'They can call me what they want'
"You're not special anymore," sang Chelsea fans, between expletive-filled chants directed at the self-styled "Special One" who they branded "Judas."
Mourinho responded with typical bravado, directing three fingers at the fans who once adored him to signal the trio of Premier League titles won with him at the helm.
"They can call me what they want," Mourinho said. "I am a professional. I defend my club. Until the moment they have a manager that wins four Premier Leagues for them I am the No. 1 ... Judas is No. 1."
There won't be any league trophy in Mourinho's hands in May, with United sinking to sixth place in his first season in charge. Instead it's heading back to Chelsea, in large part due to the revival of Hazard.
The winger was a constant danger against United, barrelling through an ineffective resistance with his fleet-footed runs even when it was 11 vs. 11.
It was Hazard who was the first to test goalkeeper David De Gea after breaking away from Chris Smalling around the halfway and beating two more United players before his 16th-minute strike. From the resulting corner it took De Gea low at full stretch to keep out Cahill's close-range effort.
Hazard was becoming a target for persistent fouling. Herrera, though, was harshly penalized for the first time after Hazard ran into him. There seemed little to dispute the yellow card shown to Phil Jones for pushing Hazard.
But on the touchline, tensions were erupting between Conte and Mourinho. Conte was furious when Hazard was fouled again by Herrera right in front of referee Michael Oliver, and the trip saw the midfielder banished.
"There were a few fouls leading up to that and was maybe slightly silly to go in and make the foul again," Cahill said. "We were complaining. We felt Eden was getting harassed."
But Mourinho was incandescent that Cahill escaped any form of punishment for a foul on Marcus Rashford, who overcame illness to fill the void left by Ibrahimovic's suspension.
The fourth official was struggling to contain the quarrelling managers and Oliver came over to the side to issue a warning.
The halftime whistle was well-timed. The touchline tempers faded after the break and Kante found the net.
United could have finished the quarter-final with nine men had the referee judged Antonio Valencia as severely as Herrera. But both a sliding challenge on Hazard and a two-footed lunge on Kante went unpunished.
And only once did United come close to force extra time. Rashford spun away from David Luiz on halfway, past the back-pedaling Cahill, but he was denied one-on-one by Thibaut Courtois.