One of the main pieces in the James Paxton deal, Erik Swanson, number nine in my preseason Mariners list, is now in the big leagues looking to help the bullpen in Seattle, although I do think there is long term starting potential in Swanson.

He comes from a very high arm slot that creates plenty of backspin on his fastball but good plane to go with it, and it can touch 97. Him staying on top of the ball allows for the fastball to have some rise to it, but he can also mix in an occasional two-seamer and get some mild run.

His secondary stuff is still just below average but both his change and slider flash at least average. My favorite of his two off-speed offerings is his change that gives some good dip and run. This allows his fastball to play even better and border on a plus pitch. The slider is solid but will never be more than average.

There is deception in his delivery, hiding the ball well, but he gets to the same release point every time allowing him to pitch with good command. He may be a piece to help out the bullpen in the short term, but I fully expect him to break into the Mariners rotation as early as this season where he can slide in as a number four of five starter and eat some innings. His stuff does not provide a ton of swing and miss, so he will have to rely on his defense a good amount, so there will be the occasional unlucky day that balls just all seem to fall into play, but overall he is a quality rotation option.

Shaun P Kernahan

Shaun Kernahan is the founder and lead writer of Three Quarter Slot, where he blends scouting precision with a storyteller’s eye for the human side of the game. Based in Parker, Colorado, he has covered baseball prospects at every level since 2013, delivering in-depth evaluations, draft analysis, and developmental insight. Over the years, he has built Three Quarter Slot into a trusted home for thoughtful prospect coverage, detailed scouting reports, and a grounded look at how talent evolves

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