Kopech threw 45 pitches during a simulated game Tuesday, working on fastball command and changeups, Colleen Kane of the Chicago Tribune reports.
Kopech's new to big-league camp this year and facing major-league hitters for the first time has its challenges. After the 20-year-old right-hander gave up four runs over one inning in his only spring appearance, Kopech was targeted for some personal instruction by pitching coach Don Cooper, hence Tuesday's closely monitored simulated game.