Haven't seen anything on this, but my working theory goes as follows:
If you open the collections page and look at the Prestige Diamond/Blood Diamond cards you'll see the 9 currently known cards you can lock in and start working towards making red through grinding stats. They are the 3 live series collection cards, (Biggio, Sheffield, Mantle) the 1st inning bosses, (Oswalt, Helton, Snider) and the 2nd inning bosses. (Carter, Ramirez, Feller)
7 of those 9 cards are listed solely by their last name. The other 2 are listed with a first initial as well as last name. (J. Carter, and H. Ramirez.) I'm assuming this is because SDS has plans to release more cards we can prestige with the same last name as these 2.
Safe to say the other Carter will be Gary, so if my theory is correct there will be another Ramirez and my bet is on Manny.
Thoughts?
.....I miss real baseball