Yeah, it's not a big jump.
I changed my mind halfway through the post and didn't finish it before sending (it's 02:45 in the UK, and I'm waiting for raws).
But I think both Lucci and Sanji are in the Queen - King gap, so a high - extreme diff win in Sanji's favour seems plausible even without any new power ups.
What does Lucci have to be Yamato level?
All of the original YC 1s had a formidable gimmick that could hold up even against Top Tiers, and Lucci doesn't seem to have any such.
He's a very complete fighter, but he doesn't have anything that really stands out about him.
An attribute of his that can hold up even against Top Tiers.
IDK, maybe speed could be it, but Sentomaru successfully blocked his sneak attack.