Luke Jackson, the righthanded pitcher who was a supplemental first round pick of the Rangers in 2010, is being moved from the rotation at AAA to the bullpen, per various reports.
Jackson has been a starter for virtually his entire time as a professional -- he's started 97 of 101 games in the Rangers' system. However, there's been talk for a while that he profiles more as a reliever long term than as a starting pitcher, and so the move itself isn't necessarily surprising, although the timing of it is.
Jackson was very good at AA Frisco in the first part of 2014, and earned a promotion to Round Rock at the end of June. He struggled badly in AAA, however, logging just 40 IP over 11 appearances, with a 10.35 ERA. The hope was that he'd show improvement this year, and he has, somewhat, putting up a 5.64 ERA in 22.1 IP over 5 starts. However, high pitch counts have continued to be an issue for him -- he's averaged almost 19 pitches per inning this year -- and there have been ongoing issues with his ability to repeat his delivery (and thus maintain his command) as he goes deeper into games.
In my writeup on him this February, I said Jackson looks like a likely late-inning reliever in the majors, though I thought the team would give him more than five starts at AAA this year before switching him to the pen. It does lead me to wonder how much the major league bullpen's struggles this year are factoring into the timing of this switch -- LuJack is on the 40 man roster, and if he shows he can pitch effectively out of the pen and on consecutive days, he could end up in the majors in the next month or two.