This is a battle of the brains and skills..
Who will wins..
I go for Itachi..
Itachi susanoo:-
Minato is super fast and his attacks is deadly but its useless against Susanoo..
He can't touch or hits Itachi
Itachi Tsukoyumi :-
Minato might be trapped inside Itachi genjutsu even before the battle start
Susano'o is a mass of chakra that has been givgen form, and guess what. so are the bijuu. point is, if minato could teleport the Kyubi away without eeven touching it, he can do the same to susano'o! and it wouldn"t even take half as much chakra to transport susano'o. the Kyubi that Minato teleported was had two times more chakra than the one Naruto has and he was teleporting not only the kyubi, but himself and a TBB.
He could also use the same sequence he used on Kurama, Food Cart Destroyer, warp Susano'o, and then deliver the blow. Or he could simply warp himself inside the susano'o, Minato teleports to the space around a sealing formular, we saw that many times during the Kyubi Attack, as long as a kunai even touches or gets close to susano'o, minatop would be able to teleport inside and attack Itachi directly.
Or simply mark the susano'o itself and then go warp inside (He marked Tobi at the back but warped to the space in front of Tobi, same principle, mark Susano'o outside, but telpeort in the space on the other side)
Not to mention the many spots that he could mark around the battle field without Itachi noticing.
I fail to understand why people always pull the Susano'o card against Minato. that technique is absiolutely easy for him to bypass, he just throws a kunai towards the thing and warps it as soon as it is within the range of his kunai....reminder....he can warp anything that gets close to his sealing formula, in other words, a kunai.
I've also heard the 'Itachi just counters Minato's kunai with his shuriken jutsu prowess, same story, the shuriken will be directed towards the FTG kunai's, which makes them easy to warp away! the Kunai's cannot be stopped or removed because whatever jutsu or weapon that you use against a kunai will be warped with either ST Barrier, FTG 1or FTG 2. there is a reason Killer Bee, Tobi, and the Raikage never tried to get rid of them you know!
The same goes for any of Itachi's ninjutsu, it can be warped away with ST easily, or Minato just teleports out of the Jutsu's range. worst case scenario, Itachi is standing near a marked location and amateresu or any of his fire jutsu is warped back to him in an instant.
The ONLY advantage Itachi has in this battle is Tsukiyomi! coz lets face the facts, Totsuka or any tai or nin attacks have opnly 1% chance of hitting, or not being redirected.
Tsukiyomi and MAYBE Izanami, both Genjutsu! It is the only reason Itachi can have the audacity to call Minato his equal, because otherwise everything else is useless!
He might not even be able to make crow clones if Minato applies the contract seal, assuming off course it is a summon based ninjutsu like Oro's hebi techniques.
Also, we have not seen what counters/lack of counters minato has against genjutsu....so we can't be sure whether Itachi's Tsukiyomi would work or not, Kabuto and gai have already showed us counters to that jutsu.
Totsuka has no chance of hitting, I don't even think this one is debatable, even if Itachi pulled off a smokescreen or distraction, it still wouldn"t work, the guy is just too fast, if people like the raikage can dodge amateresu, and kabuto can dodge susano'o arrows, then nothing physical will work on Minato, no matter how little time he has to react.
Conclusion: The winner of this battle depends on genjutsu, if it lands, or minato has no mental barriers or seals for protection against such, then Itachi would take it.....otherwise, he is the underdog!