Canelo, who is a four-weight world champion and one of the biggest stars of the sport, is looking to win Plant’s IBF title to become the undisputed super-middleweight champion.
But Plant has other ideas as the American attempts to be the first man since Floyd Mayweather in 2013 to defeat Alvarez.
And the 21-0 American was intent on winding Canelo up at the press conference as he called out Alvarez’s gym mate Oscar Valdez for having failed a drug test but not receiving a ban.
Plant said: “You’re going to find out the same time everybody else finds out. And you know when they found out? When it was too late. That’s when they found out, and that’s exactly when you’re going to find out.
“Mark my words, b***h. And you’re a b***h, too,” he then said as he directed his attention towards Canelo’s trainer Eddy Reynoso.
Speaking to Canelo once more, he continued: “What the f*** are you going to do? F*** you. And you’re a drug cheat. So tell me something. Oscar Valdez tests positive for something and not get suspended for six months. But he [Canelo] get test positive for something and gets suspended for six months, and somehow he’s not a drug cheat?”
Alvarez tested positive for the chemical clenbuterol in 2018 and received a six-month ban. He maintains the findings were the result of contaminated meat.
Canelo then replied: “Don’t make excuses before the fight,” before Plant added: “You’re a cheater. You got suspended for six months.”
Canelo wrapped up the war of words by saying: “Say whatever you say; I’ll see you 6 November.”
The pair then came face-to-face for the first time, with Alvarez pushing Plant away before the American swung a punch, which the Mexican slipped. Canelo then through a short punch of his own before they were pulled apart by security.