We spoke with the Problem Child -- who's currently the betting underdog against the former UFC champion -- about his highly anticipated upcoming bout ... and despite having a ton of respect for his opponent, Paul tells us he's out for blood once they hit the ring.

"I'm knocking this guy out," Jakey P says ... adding the fight won't last past five rounds. "I'm promising everyone that."

"Come back to this interview, everyone, after the fight, and they'll say, 'Wow, he predicted the future,'" he added. "I have a crystal ball in my room and I can see it."

Jake says he's excited to prove people wrong on Saturday night ... and has a message for those putting their hard-earned money on Spider.

"You shouldn't have done it. You should've invested into something else."

"And everyone who bet on me?? Good stuff, man. You're gonna have some dough, maybe a new car, maybe your rent paid."

Jake also dishes on those downplaying the fight considering Silva is 47 years old ... and he explains why it's actually an advantage for Anderson.