High 3/4 slot; athletic body/delivery; super quick arm; arm slot is consistent throughout game; good stride toward the plate; some effort in delivery; whips head and neck down after release; room to fill out physically.
Fastball was 97-98 (T 99) early; dipped down to 94-96 around the third; high arm slot gives the pitch good shape and plane; movement was good; ball has more life when it’s in the 94-96 range; tends to flatten out at the higher velocities; struggled staying on top of the ball; missed arm-side and high later in the game; hitters put good swings on it and got some hard contact when pitch was centered in the middle of the plate; has the look of an elite pitch when command sharpens.
Curveball was his best secondary pitch; sat 82-84 with the same arm speed as fastball; very good spin; can get on the side of ball and it can turn into a slurve; flashed the ability to throw the pitch for strikes and get hitters to chase; hung a fair share of offerings; created some ugly swings due to raw movement/velocity; future above average offering.
Changeup was much too firm early and lost most of its movement; was 90-91 and was tough to distinguish with the naked eye that it wasn’t a fastball; found the proper speed and kept it around 86-88 for most of the game; standard circle-change grip; arm speed was good; movement was decent; pitch got flat when it was left up; showed good feel for the pitch in later innings; could be an above average pitch going forward, but it’s likely a league-average pitch.
Stephenson has elite stuff with a future in the top of a rotation. The fastball is already very good, and once the command sharpens he’ll be able to move the pitch wherever he wants in the zone. The off-speed pitches are still far behind what they can be in the future, but they have at least league-average ceilings. The great stuff, athletic body, and good poise all lead to a no. 2 starter when it’s all said and done. Some scouts have even thrown the word “ace” out there, but I believe that’s a bit aggressive. If they decide to push him, he could get a cup of coffee late in 2015, with 2016 being the more conservative development plan.