Considering the type of finisher Rios is. It was a great stoppage. Brandon would have punched him through the canvas.
Yeah, refs today stop fights WAY too soon, and this fight was a prime example. It should have been allowed to go to its natural conclusion.
When he was hit with the shot that ****ed his head up and he started doing the robot, the ref's interest was peaked, he was then hit with a monster shot right on the button (afterward Alvarado looks at the ref like "WTF dude"?), you then have two more hooks that went unanswered, no reason to let Alvardo take more, there was a minute left and Rios wasn't gonna stop...good stoppage.