User blog comment:Dinosel/Chapter 871: Big Mom used thunderbolt... It was super effective!/@comment-24850639-20170706181537/@comment-24769684-20170708190609

Sanji didn't do too well against Daifuku the first time because he was focused on getting to his family asap, not fighting. Now, Daimadafuku has Smoothie and Galette backing him up.

Also, to the AWC two comments above, power scaling doesn't exist in One Piece. Everyone brings something unique to the table when they fight and fights aren't decided by a single degree of strength alone. Not to mention that Yonji didn't even fight Dai, he ambushed him to free a prisoner, and Dai seems to be just fine right now, and as I said above Sanji didn't have a real fight with Dai either.