I know the rotation is mentioned a lot in comments but I thought i'd write a fan post with my opinions and comments dedicated solely to the rotation. Also, the names i mention won't be in a particular order, so who I think should be the #2 or #3 starter isn't connected to who I put here. Obviously injuries could completely change the landscape of what everyone thinks, but lets just think about it barring injuries, since there might even be a good chance of no more injuries down the line. Finally, I think Travis Blackley will remain in the bullpen for the year, unless we have the unlikely event of actually needing a starter (highly highly unlikely).
I think you can pencil in Brandon McCarthy, Bartolo Colon and Tommy Milone for the stretch run. McCarthy is back from injury, Colon is very consistent, and Milone has been slumping in the past 3 starts but is not close to reaching his innings limit, and he has no experience in the bullpen (I don't think he would translate well to the bullpen anyways). In addition to this, he has been consistent all year and acts like a veteran so I think he should be able to get it together as soon as his next start.
Jarrod Parker is reaching his limit soon, and I doubt he could be moved to the bullpen due to lack of experience and his recent TJ surgery, but I personally think resting him occasionally (like the White Sox have done with Chris Sale) or even having a 6 man rotation works just fine. Daniel Straily is here to stay in my opinion if he is in the least bit effective; I truly doubt Billy Beane would have called him up and demoted Blackley just to have Straily make about 5 starts and be shut down for the year. I also think he won't be moved to the bullpen due to his lack of experience, though he might be the best candidate of our starters to do so, I doubt it will happen. AJ Griffin is obviously on the DL, and I'm not sure when he will be back (...?), but I think he may get a spot in the rotation based solely the production of the other 5 members (or maybe he subs for Parker if Parker is pushing his innings to the absolute max). For the last member, Brett Anderson is on rehab assignment and I think when the stats back him up in AAA, the A's should promote him and have a 6 man rotation of McCarthy, Colon, Milone, Parker, Straily, Anderson.
If the 6 man rotation doesn't work out well for the first 2-3 times around, the A's stop, but if not, I say go for it and keep McCarthy+Anderson healthy, while keeping all the others fresh. I am also very interested in listing to your opposing perspectives because I'm still on the fence about eh 6 man rotation idea, also due to the fact of having a 6 man bullpen and sending down one of the effective members (who would it be anyways if this idea did happen??)
Thanks for reading.