ESPN's John Birtwell took a trip out to the Cape Cod League (again, Insider-only).
A blurb:
In his last outing, Armstrong left after one inning due to tightness in his elbow. I don't know if Armstrong's been hurt as a result of his pitching or if his pitching has suffered because he's been hurt, but either way the inconsistency of Armstrong's body and performance are large hurdles he must overcome at the next level.