I’ve had this theory playing around in my head ever since Jack was introduced as Kaido’s right hand man.
Jack has been hyped up quite a lot; He attacked an Admiral and an ex-Fleet Admiral and managed to sink a couple of their ships. That alone gives us an estimate of how powerful he is; but Oda went even further by revealing his bounty, which stands at a staggering 1 Billion.
Many people are almost convinced that Luffy will end up fighting him, mostly due to all the hype and exposition he’s received, but by this they are overlooking Jack’s most obvious and deserving opponent, Zoro.
The way I look at it is this; Zoro has been getting the short end of the stick ever since the time skip. He is repeatedly being matched up with lackluster opponents, from Hyouzou (Fishman Island) to Monet (Punk Hazard) to the most recent joke that was Pica. Compare those fights to his early ones, like Kaku (CP9) or Mr1 (Alabasta). Those were his glory days. Sure, we like seeing Zoro as an unbeatable badass, but we LOVE his fights were he goes all out.
Everyone keeps saying that a powerful opponent will come; someone to test Zoro’s limits.
Jack is exactly the kind of person who can make Zoro bleed.
If you are still unconvinced, just look at the image in the link below. We all know how much Oda loves teasing us with his amazing color spreads. I was re-reading some parts of the manga as I typically do, and I came across this image from chapter 401.
I was honestly startled when I first saw this. We have a giant mammoth chasing the Strawhats. Luffy is in mid-air, pointing his finger at Zoro, who is removing his sword from its sheath, ready to attack the mammoth.
He’s pretty much leaving the mammoth (Jack) for Zoro to deal with.
And it wouldn’t be far for Oda to have foreshadowed this so long ago. It’s common practice for him to tease and foreshadow upcoming arcs, but I assume you guys already know this if you’ve been following the series for long.
Also these images seems to confirm:
*Theory by Kaida_94