Bubic was invited to the Royals' big-league camp Monday, Jeffrey Flanagan of MLB.com reports.
Bubic had a strong season in the minors in 2019, though he's unlikely to be ready for his MLB debut this year, as he's yet to reach the Double-A level. In 26 starts in Low-A and High-A last season, he cruised to a 2.23 ERA and a 32.2 percent strikeout rate.