This is a good fight though would have been better if Perez wasn’t a late replacement opponent. Paul Butler is a good fighter with decent technical skills but hasn’t been all that active in recent years. Perez has been very active and has also taken on tough tests.
I personally feel that Butler may be coming towards the end of his career and isn’t as motivated as he used to be so might struggle in this fight when it gets hard. This is a massive opportunity for Perez who has shown a lot of grit in his career. Perez never stops coming forward and while technically he isn’t great I think he’ll be able to overwhelm and outwork Butler who will fade late on. I expect Perez to win a decision though wouldn’t be surprised if Butler won a close fight.