A furious scuffle involving Jose Mourinho and the Chelsea coaching staff erupted at the end of Saturday's 2-2 draw at Stamford Bridge between the Blues and Manchester United.
The visitors looked to be heading for a 2-1 win only for Ross Barkley to snatch an equaliser in the sixth minute of injury time.
As the Chelsea staff celebrated on the touchline, assistant coach Marco Ianni ran past the seated Mourinho, at which point the United boss jumped to his feet to confront him and had to be held back by stewards.
After the final whistle, Mourinho went to applaud the United fans before holding up three figures to the home support – apparently in reference to the three Premier League titles he won during two spells as Chelsea manager – after they had taunted him with chants following Barkley's leveller.
United were 1-0 down thanks to Antonio Rudiger's first-half header, but produced an impressive comeback after the break, with Anthony Martial scoring twice to put them ahead.
It appeared as though Chelsea were heading for their first competitive defeat under Maurizio Sarri until Barkley turned in a rebound after David Luiz's header hit the post and David de Gea denied Rudiger.
Ianni, who was assistant to Sarri at Napoli before joining him at Stamford Bridge this year, raced up the touchline and celebrated with a fist pump right in front of Mourinho. He then ran back towards the Chelsea technical area in front of the United boss, at which point he reacted furiously.
Speaking to Sky Sports after the match, Mourinho said both Ianni and Sarri had apologised for the incident, but stressed he bore no hard feelings.
"No, I'm not annoyed with anything," he said.