Sodo Mojo Presents Seattle Mariners Top 30 Prospects: 15-11,
12. Erik Swanson
The secondary piece of the James Paxton for Justus Sheffield trade, Erik Swanson is almost certainly going to make his MLB debut in 2019. In fact, it could very well happen in the opening series in Japan.
Swanson has a good blend of upside and minor league production, making him a natural target of Mariners GM Jerry Dipoto. Swanson absolutely dominated AA, posting a 0.42 ERA in 42 innings before being promoted to AAA where he held his own, posting a 3.86 ERA.
Overall, Swanson posted a 2.66 ERA in 121.2 innings, whiffing 139 batters while walking just 29. It took Swanson a few years to find his footing but now looks to have a high-floor big league career ahead of him.
Swanson uses a fastball with two-seam movement that hits 94 MPH as a starter. Swanson also has a slider and changeup. Neither pitch is plus, but both are usually average offerings. The changeup has good speed separation from the fastball but doesn’t have much downward movement to generate a lot of swings-and-misses.
Swanson is a bit of a crossfire pitcher, which adds deception to his delivery but can also lead to inconsistent command of his off-speed pitches.
Scouts are still split on whether or not Swanson fits better as a starter or reliever. In shorter stints, Swanson’s fastball has hit 97 MPH. The inconsistency of his off-speed pitches makes him difficult to trust getting through a lineup multiple times.
For the Mariners in 2019, there is no reason to not let Swanson start to definitively make a judgment on that. The Mariners rotation is pretty well set in stone, so Swanson might have to start the year in AAA Tacoma, but might be the first guy called up in the event of trade or injury.