Sanji is going to fight vs Awakened Saint Saturn
First, all the strongest ones on Egghead Island can feel the appearance of Saturn except for Sanji.
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You might think Oda left Sanji behind the game? No, but instead, Oda spends one separate panel for Sanji vs Saturn, he is the first Straw Hat who sees Saturn.
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Second point: Oda has shown some of the awakening moments/power increase of Sanji in this chapter, but only sophisticated people can notice.
-He can easily see and hide Kizaru’s attack from a distance (future sight awakens):
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-He refuses to fight Kaku and Vice Admirals to save his energy:
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-He looks superior facing the power of science, why Oda let Luffy and Zoro appear at the same page?
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-He ripped off S-Shark’s arm, why did Oda let intact S-Hawk and broken arm S-Shark sit next to each other?
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Oda let Sanji change his eyebrows for nothing?
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My guess is that Sanji might not defeat Saturn in this arc, but he is the game changer, the life safer at least.
*Theory by traxex123