<p>(HERE WE GO!) I think the best/most notable Seidou battery (including their relationship both on and off the field) is:
</p><p>1. Miyuki/Sawamura: This battery definitely has the most chemistry and partnership (not to mention the obvious fact that they, along with Furuya, are the main trio of the story). This battery, much like Sawamura himself, is always growing and changing, most notable fact is that they're currently working together to develop Sawamura's pitch numbers. While they're on the field, they went from Miyuki leading Sawamura with the pitch calls, calming him down when the latter is panicking, to them making evil smirks and laughing together, showing that they share the same mindset in how they want to mess with the opponent's batter. At first, it is true that Sawamura is, in essence, just mindlessly throwing into Miyuki's mitt, but that's due to the former's lack of knowledge. However, even then, Miyuki seems to show understanding for Sawamura's condition. When they went up against Umemiya, Miyuki could have called for an outside pitch, but despite the risky play and despite Coach Kataoka telling him to do so, he ultimately decide to call for an inside pitch in respect to Sawamura's fighting spirit. And, later, after learning more about pitching thanks to borrowing Miyuki's books and attending his mini classes, their partnership became even more apparent in their games, showing their ability to "read" each other's minds while on the field.
</p><p>Many characters, time and time again, mentioned that this battery is quite aggressive, showing complete faith in each other's abilities. Narumiya, while watching Seidou's final against Yakushi, mentioned that Miyuki's pitch calls would have made even him flinch, but yet there's no hesitation between the battery. While watching Seidou's game against Hakuryu, Takashima mentions that Miyuki's calls are "more aggressive than usual". Mima himself compliments the battery's ability to take out runners on base and wonders if Miyuki specifically taught Sawamura to do so. Adding to this is how comfortable they are in trying out different things. In their match against Eigen (Chapter 13 Act 2), Miyuki asks if Sawamura wants to use only fastballs in this match. And the following match against Kasugaichi, they just up and tested out Sawamura's new pitch numbers simply because it seems like Sawamura's pitches are in good shape that day (even their teammates are impressed by it).
</p><p>Off the fields, they seem to treat each other more like buddies. Despite Miyuki being Sawamura's senpai, the latter doesn't treat him with that kind of respect, easily telling him to shut up or grabbing his shirt and shaking him in a comical way. Miyuki often picks on Sawamura by calling him loud or stupid, but seems acknowledge that he's doing his best to improve.
</p><p>2. Chris/Sawamura: It's unfortunate that we don't really get to see more of this battery due to Chris' injury while at Seido. While they do have quite a potential and do get along on and off the field, but ultimately, I see this more like a teacher-student battery. Chris has always been Sawamura's foundation and this battery is no exception. Yes, he brought out Sawamura's potential, but that's what a catcher is suppose to do. Keep in mind that Sawamura is just starting to learn baseball, so Chris does most of the leading, guiding Sawamura to pitch right into the mitt and comes up with a plan for their attack. So while they do have chemistry, it's not exactly a partnership. Off the field, they have more of a senpai (or teacher) and kohai (or student) relationship where Sawamura is always seeking Chris' approval.
</p><p>3. Okumura/Sawamura: I see this battery as a way for Sawamura to show is growth, especially in Chapter 123 Act 2. Yes, they get along on the field but, Okumura ends up becoming overly eager to make pitch calls like the Cutter Custom when it's way too early into the game, thus showing that he still doesn't have full understanding Sawamura's overall pitching capabilities. Sawamura ends up telling Okumura that it's better to save certain pitches for when they really need it, showing Sawamura's growth and ability to remain calm even against a national school like Seiho. Adding to that is the fact that Okumura is still not used to Sawamura's (and Furuya's) pitches so he has to brace himself everytime he catches. And as for their off the field relationship, Okumura has a more admiration-like kind of attitude towards Sawamura where he's trying to catch up to his senpai by doing his best to get into the first string team and doing what he can to bring out Sawamura's potential.
</p><p>4. Miyuki/Furuya: Quite frankly, due to Furuya's style of pitching, he doesn't exactly have a lot of variety of pitches let alone good control. It seems like Miyuki ends up being a target to catch Furuya's throws and Furuya's just a pitch machine for Miyuki. Furuya just seems content as long as he can pitch in general and, while Miyuki does praise him for how hard he works, their battery doesn't seem to have much more depth. Their interaction off the field reflects this as well where it's mainly Miyuki that tells Furuya what to do and, usually, the latter just ignores him. (Everytime I watched their battery, it just doesn't seem like there's much to dig into. I just see two individuals playing baseball rather than two working as one.)
</p><p>In a sense, I see Miyuki/Sawamura's battery is similar to Harada/Narumiya while Okumura/Sawamura is more like Itsuki/Narumiya. As for other batteries involving Kawakami, Yui, Ono and so on, there's just not enough for me to talk about.
</p><p>These are just something I've noticed while rewatch and reread both the anime and manga... and, if you made it this far, well, you have my appreciation and thanks. :D
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