Newcomb had his contract selected by the Cubs and will start Game 2 of Thursday's doubleheader against the Cardinals, Sahadev Sharma of The Athletic reports.
The left-hander was previously announced as the starter for Thursday's nightcap, and he's now officially been added to the big-league roster. Newcomb has surrendered 12 earned runs with an 8:6 K:BB across 9.1 big-league innings between Chicago and Atlanta this season.