so, for some reason, my posts don't show up. I spent some time working on this darn thing so I'm going to post here who I think is the best battery for Daiya no ace:
Chris is a phantom, something heard of but not seen. To say that the great battery is Sawamura and Chris is based on what? One game? We've never seen Chris catch in a real game. Sawamura and Chris can't be the best if we've never really seen their teamwork. It's all just hype and sentimental feelings, but I also have to say that the other commentors do a better job than me of extrapolating a ChrisXSawamura battery.
I think that we get more of a feeling for the Chris legend from Miyuki than we do from Sawamura's relationship with him, it's just that it's half-hidden. More than Sawamura, Miyuki loves Chris. I think it's easy not to see it, but Miyuki says it over and over, how lucky Furuya is to have Sawamura. That wistful statement is about his broken heart over missing the equivalent rivalry, mutual learning experience, and closeness with Chris. Miyuki carries this loneliness all through his high school years, it's just really easy not to see that while the best, he'd trade that high position for a lower one next to Chris. We even see it symbolized when Miyuki stands alone and apart in every crowd scene.
The point is, we're influenced by what is said more than what is subtly shown, so we get a strong sense that SawamuraXChris would be a great battery. We just don't have any evidence to confirm it. I think a lot of that influence comes from Miyuki's loss as much as what we actually see from ChrisXSawmura. It's also easy to forget that Sawamura was assigned to Chris. There wasn't a choice, and that Miyuki was assigned to Furuya. The favoritism isn't favoritism at all. It's Miyuki's job, and he doesn't have a choice but to look after and mentor Furuya.
When it's MiyukiXSawamura, the picture is slowly resolving to crystal clarity that they fulfilling theirs as well as the author's destiny as the best battery. In Act II, Miyuki announces to the team and the world that he is determined to exceed Sawamura's expectations. I think we'll see them go to their full potential as the close of Act II nears.
MiyukiXSawamura is the ideal battery. All the rest are either phantoms of the past or future. To speculate on any other battery equals a fun exercise but nothing more. With respect to the other commenters, I submit these as my opinions.