Look at this article from a month ago:
Bullington said he was experiencing the "same feeling" in his shoulder as he did in April. Bullington began the season at extended spring training and didn't make his debut with Class AAA Indianapolis until May 11.
Does anyone know what might have happened here? Is it possible Bullington has had this injury all year and just hadn't been tested for it until last week? Because that's what this sounds like.
Thanks to Eric for the tip.