Greentext

IIRC the chimp thing is a bit overblown. I seem to remember that chimps are something like 1.3-1.5x stronger than humans per body mass. However male chimps weigh in at only around 40-70kg.

These are average numbers, so assuming a top ranked fighter is significantly stronger per mass than the average human (my amateur experience suggests that a well trained man is around 1.3x as stronger than average per mass). Matching a top ranked heavyweight fighter (≈110 kg) to a higher-end chimp means the human is probably around (1.3 x 110 / 1.5 x 70) = 1.35 times stronger than the chimp.

The top ranked fighter has a reach advantage, and while chimps are robust, I would almost call it absurd to suggest that a well landed kick from a top-ranked 110kg fighter would not injure a 70kg mammal.

The chimp has the advantage of biting, but even in a ground-brawl, I have a hard time seeing a chimp with the strength of an average 105kg man standing much of a chance against a heavyweight MMA fighter, just by knowing how completely one-sided that fight would be between humans. I don't think the bites of the chimp can overcome the large strength difference and massive technical difference (chimps are similar enough to humans that ordinary BJJ techniques can probably still be used). All this is assuming that the chimp is able to get within reach without catching a crippling strike first.

Note that the above takes a higher end chimp vs. a top ranked fighter. Taking an average chimp and I definitely cannot see the chimp standing a chance. That would be like betting on an 85kg guy without fighting experience beating an MMA heavyweight. Even if the guy has a knife, he'll probably be knocked out before even touching the fighter.

Of course, being an average man myself, I would definitely be torn to shreds by even a lower-end chimp.