Don't count on Tito Ortiz and Anderson Silva grabbin' a beer after their upcoming boxing match ... 'cause the UFC legend says he's lost ALL RESPECT for Spider after contentious contract negotiations.
46-year-old Ortiz broke down the beef when TMZ Sports talked to him at RVCA Training Centre in Costa Mesa, CA ... explaining how Silva demanded the fight go down at 195 pounds -- 10 pounds under the weight he last fought.
"He wants me down to 195. He's fought at 205 over 6 times in his career and he wants me down to 195. So, it shows that he's afraid of my power."
That's an issue 'cause it means Ortiz has to cut extra weight and deplete his body before the fight -- and frankly, that ticks Tito off.
"I lost respect for the guy man. He's one of the best in the world in mixed martial arts, but I have no respect to him."
The 2 legends are fighting September 11 on Triller... a card that also includes Oscar de la Hoya and Vitor Belfort.
Silva is coming off a big time win in the ring over former boxing champ Julio Cesar Chavez Jr. ... a fight that shocked many experts.
But, don't count on the impressive performance scaring Ortiz ... he's veryyyy confident he's gonna whoop Silva's ass.
"Am I the toughest fighter? I'm way tougher than him, 100%. Am I gonna make it vicious? Am I gonna make it just a blood fight? Yes. I hope he's ready for a dogfight. That's what it's gonna be. It's gonna be a dogfight."
"I ain't in here for an exhibition. I'm not here for pitter patter, you know, do a dance. I'm here to fight. I'm a fighter."
We also talked to Tito's boxing coach, Jason Parillo-- one of the best trainers in the sport -- who told us the key to beating Silva.