Jinbei and Whoswho are fighting because Jinbei stayed behind to hold Whoswho and his goons in order for Luffy to keep moving.
The "behind the mask" thing was thrown there. Didn't have any setup prior. "lmao"?
How the fuck is this the same thing?
And even if it is, why two different characters need to have the same kind of "connection" to their enemies? Is there a rule about that?
Dude fought Kuroobi just because.
Dude fought Mr2 because he was chasing Vivi.
Dude fought Jabura just because he needed to step up and save Usopp.
Dude fought Absalom to rescue Nami. With the invisibility gag.
Dude fought Wadatsumi because he made Nami fall.
Never this "weird ass past connection to someone he knew" was necessary.
I'm NOT saying it can't happen. What I'm saying is that it is a weak ass "setup".
Past connection is not solidifying the match-up, but it gives more concrete evidence than just a simple clash. If Oda hadn't made that connection between Jinbei and Who's Who, 99% of people here would think that Who's Who is just a temporary match-up for Jinbei. But one random line and bam, Jinbei is like 90% locked with Who's Who. Because the connection needs "pay-off". Oda is not gonna give a "throw-a-way" line like "I know your past" or "I know you are the son of Judge" for it to never mentioned again later in the story.
Heck, even Queen mentioning Zoro has pay-off, with Zoro scaring the fuck out of Queen.
So all and all, the whole Judge's son has to come back again.
And clashing once means little, even Izou clashed with King.....
So, i'm not claiming that Sanji will fight King, or Queen, or Jack. But still, "Judge's Son" is still a better evidence than "clashing once".