amaterasu is almost instant but then there is always a process, one eye is covered and the other eye starts to bleed, which means after the first hit, it will impossible to hit minato twice with the same jutsu. and if minato gets hit, he could easly seal the fire, he is a master seal
Minato can surely seal the flames, im sure he has the seal formula to do so.... but you seem to think that Minato will only have to deal with the flames.
While he has to get the scroll out, draw the seals and procceed with the sealing, Itachi is still there, and he wont be nice enough to just stand there and do nothing. That means that Minato needs to Hiraishin non-stop as he was previously doing and he will need to suffer from Amaterasu on top of having to get the scroll out and proceed with the sealing.
There is no ''Minato would easily" seal the flames, if Minato gets hit with Amaterasu, shit is hitting the fan big time, and even if Itachi doesnt hit him with anything instantly, it means Minato will have suffered significient damage from Amaterasu and would have used a shit ton of Hiraishin in order to not get it.
Also, you act like Minato as an answer for everything when it comes to Itachi's arsenal, as if he knew exactly how to deal with him, but you do realise that he is facing a tactical genius and the best Kunai user or even weapons overall of the manga?
If there is someone that is smart enough to spot a jutsu's weakpoint in an instant it's Itachi, and Itachi is the perfect counter when it comes to Hiraishin.
If Itachi knows that he can't let Kunais near him because it would be dangerous, you can be sure that Kunais will never be anywhere near him as the guy is simply unmatched when it comes to using Kunai precision and deflection.
And don't go and say Minato will be fast enough even without Hiraishin, Minato's movement speed isnt enough to outclass's Itachi very fast speed on top of him having the Sharingan.
This whole fight can only happen if Minato doesnt look in Itachi's eyes and if he uses Hiraishin constantly.
I always gave this match up a tie as i feel they are very similar in so many ways... but a lot make it seeem like circumstances are on Minato's side, what i mean by that is ;
Minato apparently having knowledge on Tsukuyomi, Amaterasu and Susano , which is something that i complety disagree with.
Jiraiya, someone who was more experienced and knew much more about the world than Minato, had no ****ing clue what was the flames (Amaterasu) Itachi used in part 1.
Minato was young, and even tho he had MAYBE heard of Amaterasu and Tsukuyomi and Susano, he never saw it wth his own eyes... just like Jiraiya never did.
The mangekyo had only been seen in an era that took place in Madara's time... as we have no knowledge of Uchihas awakening the MS except for Madara,Izuna', Shisui, Itachi, Kakashi, Sasuke and Obito. And even among these... only 3 that we know actually awakened up to Susano.
Minato never had to fight the Sharingan like Gai trained himself to do... and thats why he was the only one who thought of never looking at the Sharingan itself during combat.
Even Kakashi, who is pretty much s smart and both Itachi and Minato.... never thought of this, Minato being Minato doesnt guarantee that he will do the same thing.
So to me it all depends on how you make this fight work....
Do both shinobis have knowledge according to what they know in the manga or do you give them a set amount of knowledge on each other.
If both knows everything about each other then i say that Minato will be at a disadvantage as Itachi is perhaps the most versatile ninjas in Naruto (Speed, Intelligence, Deadly ninjutsu, Best genjutsu user......)
While Minato is versatile but due to ONE jutsu.... if that jutsu is kept at bay (as Itachi can do it with his speed / Kunai expertise) Minato has nothing but his movement speed and Rasengans to avoid Itachi's MS and all his crow clones plays and finger genjutsu.
If both ninjas know that they know according to the manga...well I would trust Itachi knowing more about Minato than Minato knowing more about Itachi.... as Itachi is apparently the only one outside of Kakashi and the Hokages and JIraiya that knew that Minato was Naruto's father.... and he also knew why Minato actually had gotten to where he was (Hokage) even tho he was 5 years old when Minato died.
Itachi is the wisest and quite possibly the smartest ninjas here,,,, and while you claim that Minato may be smarter,,, it's possible but feats are clearly on Itachi's side here.
Itachi has more chance to know about Minato than MInato knows about Itachi.... as Minato never had to fight the Sharingan, and even if he did, he never faced a mangekyo user and perhaps never ever saw one as there is to our knowledge only a handfull of Uchiha who ever awoke the Mangekyo in the history of the Uchiha clan.
I always gave this match up a tie, perhaps because i feel like they are equally badass (even tho i like Itachi more)... but i feel like people underestimate Itachi's abilities and knowledge and give more advantage to Minato that he actually shouldnt have (prior knowledge of the Mangekyo)
Also, Minato doesnt have Sage mode or hell... even if he does... we saw against Obito that he didnt have time to go and attempt to summon them.... as we saw with Jiraiya that summoning Ma and Pa takes quite a long time.... against someone as fast and deadly as Itachi.... it wouldnt be any different than against Obito.... and it would actually be quite worst as Obito has one and only one jutsu in his arsenal, while Itachi is overall much more dangerous. Obito is strong but he's a one trick poney (without the Rinnegan).