Pereira is much, much better than Rountree. I don't think Rountree has grappling nor wrestling to even try. Doesn't even have cardio advantage either obviously. Pereira is much better version of Rountree, like every shape or form imaginable. Hell, wouldn't even surprise me if Pereira is even a better grappler. He probably is.
I do think Pereira knocks his ass out in first couple rounds, but when you can knock out Saki, yes I know Saki didn't adapt his game well like Pereira, but believe me you, if you can knock out Saki, you can knock out Pereira, who's been hurt and put lights out before.
You count people out at your own peril, in this heartless game. Hope Alex isn't looking past him. I think if they fight 10 times, Pereira wins at least 9 times. But it'd be mad to look forward to other fights after.