I'm guessing this is a rehab start for him, don't know for sure. I would hope he is not viewed as a AA player at this point...but I don't know.
The irony in this for me is that I saw him pitch a rehab start here for the Mudcats two years ago when the Mudcats were a Florida AA affiliate. While with Detroit, Miller was traded for one of the most successful Mudcats of all time, Miguel Cabrera. The guy is back but sitting in the 'other' dugout this time. I'm thinking Miller may not be the guy he was projected to be back when.