Thornton was placed on the 10-day injured list with right elbow inflammation.
It's unclear when the injury cropped up, but it could help explain Thornton's struggles in his two starts since the All-Star break (0-1 with an 18.69 ERA, 2.77 WHIP and 3:4 K:BB in 4.1 innings). The young right-hander will now remain sidelined for at least the next 10 days. In a corresponding move, Ryan Borucki (elbow) was activated from the IL.