the chicago cubs selected berg in the sixth round, with the 173rd overall selection, of the 2015 mlb draft. berg signed and spent 2015 with both the eugene emeralds and the myrtle beach pelicans, where he posted a 2–1 record with a 1.40 era. in 2016, berg started the season with myrtle beach and was later promoted to the tennessee smokies; in 43 total games between both clubs, 4–4 record and a 5.17 era. he spent 2017 with tennessee, myrtle beach, and the iowa cubs, pitching to a combined 4-4 record and 5.16 era with a 1.38 whip in a career high 61 innings pitched between the three teams.