The Blues are understood to have been left appalled by the conduct of the Portuguese giants, who they say tried to antagonise Chelsea players and staff throughout Tuesday's encounter, says the Daily Mail.
The managers' clash erupted after the final whistle as members of both teams then confronted each other on the pitch as tempers flared.
Defender Pepe could be seen confronting the Blues trainer, and the pair had to be separated by one of the officials.
Reports in Portugal indicted it was sparked by Chelsea boss Thomas Tuchel telling his rival Sergio Conceicao to "f*** off" - but those claims have been strenuously denied by the Blues and branded "complete nonsense".
In contrast, sources claim Conceicao appeared intent on antagonising the Chelsea bench throughout the night, gesturing intermittently towards his opponents' technical area.
The Portuguese boss was also visibly applying pressure on the pitch, Porto players are claimed to have used "industrial language" throughout the game in an attempt to wind Chelsea players up - though this is not uncommon.