As I said in spoiler thread, if they clash I see only two scenarios before Yamato most like shows up and fight herself against Jack.
- Jack beating Sanji(with increase Jack hype)
- Jack and Sanji fighting equal(in case for both hype)
I don´t see Oda trashing Jack again after losing a battle at the rooftop, in sense of tension and villiian character building, it doesn´t make sense to use Jack again as hypepool.
That would be like Doffy losing against Sanji and later against Law only for getting back in final battle against Luffy? After taking two Ls what would be the tension of defeating Doffy who was already beaten twice? In that case the same could said about Jack, I don´t see him losing against Sanji who is his not final opponent.