Lesko (elbow) will make his pro debut Tuesday in the Arizona Complex League, Kiley McDaniel of ESPN.com reports.
The best prep pitcher in last year's draft class, Lesko had Tommy John surgery last spring, and he will be eased into pro action against rookie-level hitters. Assuming his stuff is back to where it was pre-surgery, Lesko should quickly ascend to Single-A Lake Elsinore.