Truth is
@King Moe that Vergo was trolling Sanji who was healthy. Let me demonstrate
First half of the fight
Vergo gets blindsided by a fully powered up DJ and literally doesn’t give a fuck.
Next thing he gets hit by Sanji but here is where he arguably doesn't give a fuck about him hitting him, as there is no "?!!" or "!" coming from him so he literally gives no fuck. He might've even let him hit him (it's not unthinkable given the evidence I will demonstrate below). The exclamation points are coming from the marine spectators who comments on the fight before and after the second hit connects on the "fake Vergo" and how well Sanji performs against him.
The second half of the fight
Now here is where so many people stop analysing properly and I will clarify what is actually happening here for the spee D. readers out there who gets this wrong, I will explain what Vergo really did here. It's obvious from the stance here that Vergo is preparing for a roundhouse kick with his left leg, yet when their legs clash it's not from a roundhouse kick from his left, but it is actually their right legs that are clashing!
As you can see here, he prepares a roundhouse kick with his left leg as per the raising of the leg and the shifting of his body radially outwards to produce the necessary torque for this attack (as such not a fast-forward charge as the anime has it, they do their own shit with this whole clash). When he says "don't get in my way" he is about to advance, Sanji then answers back to him, and when Vergo has advanced the necessary launching distance he ostensibly goes in for the roundhouse kick (Sanji prepares the block for it) but the very next moment before Sanji can even react to it, he does not follow through with the execution of that kick, but instead shifts his entire center of mass over to the left leg and goes in for the clash with his right leg(!) That's the real kicker here, as it were, where Vergo switches from building up an attack from the left, to then switch gears completely and moves his entire body mass and attack over to the other leg! As per the highlighted red markings around his leg here that indicates this is an action that happens on the spot; this took Sanji by complete surprise as per the three exclamation points (!!!)
It's clear as day that he was prepering for a roundhouse kick, so why does he not recruit this mass and bodily torque to produce a powerful attack from this? By switching to his left leg and blocking ("attacking") with his right leg, he not only loses the momentum and the power he was building up, but the position itself (standing with one of your legs in front of the other perpendicular to it) is a horrible position where he has no stability, the posture is terrible and no base, as such the center of mass is off but with no trade-off as there is no power being gained from this! Why would he do this?
Not only is it a block, but it is a block with no power as he
deliberately switches his body over to the other side and as such is losing all power; in theory this move has no real power behind it and Sanji should really be able to push him back from this. Not only does he not achieve this, but his tibia gets almost broken in half from the impact of them clashing their legs like this where Vergo deliberately makes sure not to leverage any physical power wiht his body, instead nerfing himself by just holding up his leg to block from a shitty position! The result was still one where Sanji almost had his tibia broken in half!
The answer to why Vergo would do this becomes quite obvious: he was trolling Sanji! He was demonstrating how he was faster than what Sanji could react to as he was switching position from ostensibly doing a roundhouse kick to a block from a shitty position, just to mess with his head. Not much unlike how he mid-battle uses his bamboo as a blowgun against Smoker (which has Smoker sweating buckets from this) not because it is an effective weapon in and of itself (Smoker being fast enough to dodge the explosion lol) but because it demonstrates his skill with armament haki, ie combining the elasticity with armanment hardening which point to his armament being exceptionally strong, hence why Smoker was worried from this. As such, Vergo is flexing with Sanji here to show who is really the punk in Punk Hazard (sorry for the pun, just know that Zoro would do worse). Vergo is not only faster here, but his leg is so much stronger that he can break his leg by applying no active force himself! It's a demonstration of power simply put. Vergo had the real terminator theme going for him here with Sanji commenting on his iron body (not tekkai by the way, just his constitution) and what follows from there is a continuation of that.
The anime has Sanji straightening out the leg from their clash, but that's not what happens in the manga. Nothing can be gleaned from the manga that supports what the anime did. Sanji's leg is pointing straight up right after he is seen groaning in pain here. The best way to look at this is that Vergo broke up the lock position in this way which left Sanji like this with his leg pointing straight up, while in the meantime Vergo is already swinging his
left leg around in a clockwise direction to deliver a reverse roundhouse kick (as opposed to taking advantage of the opportunity to just deliver a front kick) and this goes by so fast that Sanji struggles to dodge it while Vergo looks bored and casual as fuck. Not only this but his kick is so fast that it actually heats up the air which I highlighted there! That's how fast it is, with Vergo doing this casually.
Casual-as-fuck Vergo didn't give a fuck about landing a straightforward kick, but no instead he is so fast that he can deliver a reverse roundhouse kick while Sanji is standing there rather haplezzly like a fool with his leg in the air. Vergo was trolling and playing with Sanji the latter half of the fight, this becomes quite obvious and this is the only sensible conclusion, him shifting his leg like that, playing and trolling with Sanji. Sanji is slowly but surely losing while Vergo is taking his time playing with his victim.
Vergo arguably shat on Sanji here, and mid-battle the announcement went off that had Vergo thinking and monologuing about Trafalgar Law in the middle of fighting Sanji. Vergo put literally no effort into the fight and the announcement is the plot device that saved Sanji's life! See the exclamation point from Vergo as he is seen listening in on what is going on while paying Sanji no mind, and the next moment he starts monologuing about Law. One clash in the background where Sanji's leg is breaking apart from the sfx of their cclash, then the announcement comes in and Vergo starts monologuing about Law
Next thing Vergo goes his seperate way to stop Law while Sanji from a couple of clashes where Vergo was trolling him has Sanji stressing out about his leg, Oda focusing in on Sanji's leg and the marine soldiers being so worried about how his leg was making creacking noises, while all visible injuries from Sanji's attacks are gone from Vergo next time we see him who has all but forgotten about Sanji's existence.
So to summarise, this was a complete stomp! Vergo was faster than Sanji, he was nerfing himself in the clash and still nearly breaking his tibia in half from this; he was faster than Sanji as the trolled him twice like that showing how Vergo has a real sense of humour actually (Oda made him with two funny character quirks and this evil twist of his is one I can get behind!). Vergo didn't use any armament, he didn't use any of his rokushiki techiques, and he never used his bamboo. Again, not only was it a complete wash, but it would be the equivalent of a Kali master going up against a professional Muay Thai fighter and trashing his leg while putting in minimal effort. I think Sanji is stronger than Zoro in PH and Vergo dominated Sanji here, so imagine the result of Vergo going up aganst Zoro who is a swordsman when he is the equivalent of a kali fighter dominating a Muay Thai fighter at his own game. Sorry to break it to you, Terminator wins and Zoro dies horribly!
We can tell it is his right leg just by seeing how the inside of the foot is on top, not the left leg.
