After a whirlwind spring, including a March 1 trade from the Dodgers, as well as making his major league debut in Houston on April 5 in which he surrendered a game-winning, three-run home run to RF George Springer, De Jong is settling in nicely in Triple-A Tacoma, with a 1.74 ERA and 10 strikeouts over 10 1/3 innings in two appearances.

De Jong displays above-average pitchability, with a big mound presence with a good feel for sequencing, and average command and plus control of his arsenal because of an easily repeatable delivery. These attributes will be paramount for him to reach his ceiling of a number four starter, as he doesn’t dazzle hitters with any single plus offering on the bump.

He operates with a fringy fastball in the 88-to-92 mph range, but he has plus command of the pitch and does a nice job of elevating it in the when he needs to. De Jong also showed an above-average curveball with 11-to-5 shape and downer action at 73-to-75 mph that he was able use early in the count, and use as an out pitch, and confidently toss it for first-pitch strikes.  He also dialed it up into the 76-to-77 range at times, giving it a more slurvy look with tighter spin.

He seldom used the changeup, but the pitch sits 82-to-85 mph and is presently fringe-average, coming out of the fastball slot.  It has the potential to develop into an average pitch with increased use, and because it comes out of the fastball slot with the arm action. De Jong showed some feel for the pitch, occasionally spotting it down in the zone, but it lacked any notable movement in this viewing.

At 26 years old and having already made his debut, the Mariners probably view De Jong as a close-to-finished product at this point.  He could be a nice depth piece for the Mariners should they encounter injuries over the course of the long season. However, it also wouldn’t be a surprise to see him dealt if the M’s are buyers at the trade deadline, should they still be in the race for a wild card spot come late July.