Avila exited Thursday's game with what appeared to be significant arm injury, Jeff Sanders of the San Diego Union-Tribune reports.
Following a rehab stint in rookie ball, Avila was activated from the injured list Thursday to make his first appearance for Double-A Amarillo since a right elbow strain shut him down in late April. He made it through 1.1 innings, giving up five runs (four earned) on four hits and two walks, before falling to the field and writhing in pain after throwing a pitch. Although he was able to walk off under his own power, the injury appeared to be serious. An update on his condition has yet to be released.