Rated No. 154 in MLB.com's Top 200 Draft prospects, McCanna watched eagerly from his home in The Woodlands, Texas, expecting to be taken on the second day of the MLB Draft, only to fall to Houston at pick No. 379.
Both McCanna and Astros director of amateur scouting Mike Elias were surprised when the local right-hander was still available in the 13th round, and Elias pounced on the lifelong Astros fan.
"I have no idea," McCanna said shortly after the Draft concluded. "I was ready to sign. I'm ready to play and I think that's how the Draft worked.