Cantillo will be part of the Padres' 60-man summer camp.
Cantillo has a chance to develop into a No. 3 or No. 4 starter if all goes well in the coming years, but he has only made three starts at High-A, logging a 4.61 ERA as his walk rate spiked to 11.1 percent, so he is not ready to face MLB hitters. His inclusion was more for developmental purposes than to help the big-league team win games in 2020.