Liverpool manager Jurgen Klopp appeared to admonish members of his backroom staff and players on the bench after they applauded when Andreas Christensen was sent off during their game against Chelsea.
With the scores level at 0-0 at Stamford Bridge heading towards the end of the first-half, Blues centre-back Christensen hauled down Sadio Mane as he ran on to a Jordan Henderson through ball.
The Dane was initially shown a yellow card by referee Paul Tierney.
But after he was advised by VAR to check the pitch-side monitor he changed it to a red, with Christensen adjudged to have denied Mane a clear goalscoring opportunity.
After the decision was changed, some in Liverpool colours reacted with joy on the bench, but were swiftly told to wind it in by Klopp.
Klopp turned round from the touch line and shouted back at his bench: “Are you crazy? We never ever do that, OK?”'
It is not yet clear exactly who the guilty party were, but Klopp is clearly keen to ensure his team do not gain a reputation as one who play by the dark arts this season.
His strong reaction comes after he and Chelsea manager Frank Lampard clashed on the touchline in a game between the two teams in the last campaign.
During an eventful night at Anfield in July, Lampard told Klopp and his assistant Pepijn Lijnders to "f*** off" and launched a tirade in the direction of the Reds bench.
The touchline spat began over a disagreement about a foul and the Blues boss also added: "One title you've won and you’re f*****g giving it the big 'un".
