Jose Mourinho and Ole Gunnar Solskjaer had reportedly already had a blazing argument before they took aim at each other after Manchester United's 3-1 victory against Tottenham.
The two managers had been ramping up the mind games ahead of the match, but things came to a head in their post-match interviews.
After Solskjaer accused Spurs forward Son Heung-Min of "conning" the referee in an incident which saw a United goal disallowed, the Norwegian added: "I have to say, if my son stays down like this for three minutes... he won't get any food."
Mourinho was furious with this remark, and retorted: "If you have to steal to feed your kids, you steal. I am very, very disappointed, and like we say in Portugal bread is bread and cheese is cheese, I told Ole already what I think about his comments."
According to Football London, however, tensions had already begun to rise between the two during the clash between their sides before the media duties after the game.
They report that the pair had a 'fiery encounter' on the touchline in the first-half, but managed to temporarily patch things up in the tunnel at half-time.
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Quite the rivalry appears to be developing between the two, but given what happened on the pitch it seems it is Solskjaer who has the upper hand.
And it remains to be seen if Mourinho ever faces him again as Spurs manager, with his job in North London believed to be under serious threat.
The weekend's result saw Spurs fall to six points behind fourth spot, and it is looking increasingly unlikely there will be Champions League football at the club next season.