Seattle Mariners Acquire Marco Gonzales from St. Louis Cardinals

The Seattle Mariners have struck a deal to land starting pitcher Marco Gonzales from the St. Louis Cardinals in exchange for Tyler O’Neill.

According to Mark Polishuk of MLB Trade Rumors, the Seattle Mariners have acquired left-handed starting pitcher Marco Gonzales from the St. Louis Cardinals. In return, the team has sent top prospect Tyler O’Neill to the Red Birds.

Gonzales, who turned 25 years old back in February, is a former top prospect who has fallen from grace in recent times. The 19^th overall pick in the 2013 draft, the St. Louis Cardinals initially had high hopes for his future. Indeed, he dominated in the minor leagues, surging all the way to crack into the big leagues in late 2014.

Since then, however, his work has been decidedly less than stellar. The lefty owns a 5.52 earned run average over 40.2 innings of major-league work, and advanced metrics echo the pessimistic view of his ability to prevent runs. Part of the problem lies in his control, as he has issued 22 free passes against just 34 strikeouts in that time.

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Injuries have also been a problem in his thus far short MLB career. Gonzales was on the shelf for a large portion of 2015 with shoulder issues, and a torn ulnar collateral ligament in his left elbow completely derailed the following season.

Still, Gonzales is a promising young arm, and Jon Morosi reported just a few days ago that this was a priority for the Mariners. Now, it appears that they have acquired a player who fits that mold. His short-term value may not be so high – the team is set to start him with Triple-A Tacoma – but Gonzales should certainly factor into the starting rotation mix in the coming seasons.

All this potential, however, comes at a cost. Tyler O’Neill is a clear-cut top-100 prospect, with MLB.com valuing him the highest at 36^th overall with Baseball America and Baseball Prospectus following suit, pegging him at 38^th and 53^rd overall, respectively. If nothing else, O’Neill brings a ton of power to the table. He has already slugged 19 bombs alongside a .235 isolated power for the Seattle Mariners’ Triple-A affiliate this season.

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O’Neill may be three years younger than Gonzales, but he likely fits the same development stage as his counterpart in the transaction. An outfielder by trade, he is now joining an outfield that is seemingly full. The Cardinals might try to move an outfielder either in the coming days or this winter to open a starting job for the slugger.