The Rangers are apparently contemplating promoting John Danks, Thomas Diamond, and Edison Volquez from high-A Bakersfield to AA Frisco.
All three starting pitchers would most likely join the Frisco rotation, meaning that the current Roughrider rotation of Wilfredo Rodriguez, Josh Rupe, Nick Masset, Matt Lorenzo, and C.J. Wilson would have to be seriously re-worked.
The DMN piece speculates that Rodriguez could be moving into the Oklahoma rotation to make room for one of the new additions. Rupe and Masset are the two most highly regarded pitchers of the other four candidates, although only Rupe (from that quartet) has pitched well at AA this season. Wilson and Lorenzo could end up joining Agustin Montero and Juan Dominguez in the Frisco pen, although personally, I'd just as soon Dominguez be moved to the Ranger bullpen, anyway.