A red mist descended over Ashton Gate where a mass brawl erupted moments after the final whistle.
Furious players and staff from both camps were pushing and shoving on the touchline as the promotion race boiled over following a tense contest.
Victorious manager Alex Neil and City gaffer Gerhard Struber were in the thick of it in astonishing scenes that mean both clubs will be in hot water with the FA.
And a war of words ensued between the pair after things kicked things off – over post-match handshakes.
Neil led the way by blaming Struber and Irish midfielder Jason Knight for sparking the melee.
“I went over to their coach to shake his hand after the game, as I do with every game and he sort of pulled his hand away, which was disappointing,” Neil said.
“I don’t know if Jason’s looked and thought that I’ve refused to shake his hand, which is obviously not the case, but he’s come over and pushed me.
“And then there’s just been a swarm of people came from all angles and handbags.
“Everybody’s pushing and shoving and all that sort of garbage that happens at the side of the pitch.
“I’m not crying over it but the first thing I always do is shake the opposition’s hand, irrespective of how frustrated I am.
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“So, it is what it is. It’s going to be investigated but we certainly weren’t the instigators. I’m more than comfortable with what happened.”
Struber was understandably incensed because his goal celebrations had just been cut short as the Robins play-off push stalled.
Zak Vyner’s smashed in a stoppage-time shot but Ross McCrorie was incorrectly judged to have nodded the ball back from an offside position.
That would and should have cancelled out Mihailo Ivanovic’s fourth goal of season.
The Serbian striker hammered the ball in on 59 minutes after Radek Vitek had denied Femi Azeez in quick succession.
Millwall skipper Jake Cooper kept City at bay with several key blocks in a sterling defensive display.
And goalie Max Crocombe pulled off a stunning late save to push McCrorie’s drive around a post as Millwall strengthened their grip on third spot in the table.
Struber, who called for VAR in the Championships, had another exchange of words with Neil as the Scot exited his press conference and then went on the offensive.
Struber laughed”It’s a really big joke.
“I will make this crystal-clear – I showed him my hand twice and he was not ready to shake hands.
“I asked him now: ‘Why you give me not your hand?’ And he goes, ‘Why you give me not the hand?’
“This is crazy, I look in his eyes, and I give him my hand, but he goes two times away. I hope we find pictures but I cannot say why the emotion goes over.
“Two football styles come together with a lot of pressure, first duels, second ball fights and in the end, the kick-off was a wrong decision.”
