Most one-sided upset of all time?

[Hulk]

Acelino Freitas vs Michael Oliveira. He had been retired for 5 years and was fighting 4 divisions above his bsst. Freitas still fucked up the punk kld Oliveria

Edwin Rosario - Livingston Bramble was one.

Rosario was not that big of an underdog.

Yes news of the Freitas fight was astonishing and reading about it put a smile on my face. I believe I was able to see some of it on youtube as well. Unbelievable. But, even faded world class fighters will put a beating on guys who are simply wannabees who lack 1/10th the natural talent of the older former champion.