Welcome back to my annual off-season series that has a quick-and-dirty review of all 30 minor league systems around baseball. This feature began way back in 2008.
If you were perusing this series back in 2015 you would have read:
The Riser: Dan Altavilla, RHP: Altavilla, 23, doesn’t have a huge ceiling but he had a very promising year and the organization didn’t see that much in terms of huge prospect value spikes in 2015. The under-sized righty can touch 96-97 mph with a promising slider and showed a propensity for the strikeout while playing in a tough league for pitchers (The California League). The consensus seems to be that Altavilla is bound for the bullpen but Toronto’s Marcus Stroman has shown that size really doesn’t matter — but the Mariners prospect will need to create better plane on his offerings to mimic the Blue Jays’ breakout star.
Now on to the new stuff:
First Taste of The Show: Matthew Festa, RHP: The Mariners didn’t rely heavily on the minor league system in 2018 so the rookie contributions were pretty thin. The most intriguing player for future value is Festa. He has a nice fastball-slider combo with a couple of other offerings he can sprinkle in for fun. His ceiling is probably seventh-inning guy but he could be a solid-but-unspectacular contributor to the ‘pen if continues to throw strikes and keep the ball down.
The Draft Pick: Jarred Kelenic, OF: The Mariners own first-rounder, Logan Gilbert, didn’t actually pitch after signing (which is no fun) so let’s talk about Kelenic instead. As most Mariners fans know, he was acquired from the Mets in the (questionable) Edwin Diaz deal. As a cold-weather prospect, Kelenic was considered a bit of a project but showed a better eye than expected and his 22-39 BB-K rate in the Appy League was encouraging. The ball also jumps off his bat and he should have an exciting mix of power and pop when he reaches the Majors. Look for him to jump up to full-season ball to open 2019.
The Riser: Evan White, 1B: A gifted fielder at first base, the big question around White has always been around his offensive potential — especially in terms of power. He made adjustments in 2018 to try and hit for more power, which included lowering his hands. I’m not a fan of this move as he showed less consistent contact after making the move — although he did drive the ball more when he hit the ball on the screws. I’m curious to see how he performs in double-A in 2019 and if the trade off on contact continues to improve his offensive profile.
The Fallen: Kyle Lewis, OF: Taken 11th overall in 2016, Lewis has never really recovered from a terrible knee injury that caused him to miss significant develop time. He has a below-average approach at the plate and posted a 28-87 BB-K in 86 games in 2018 split between high-A and double-A. His best offensive tool is his power but his contact is below average mostly because he doesn’t wait out the pitcher and swings at too many questionable pitches. He also has a big, long swing and has a lot of unnecessary movement in his arms and bat prior to swinging — often causing him to have an inconsistent swing plane. Lewis, 23, has a lot to prove in 2019 as he returns to double-A.
The 2019 Contributor: Erik Swanson, RHP: Swanson has now played with three organizations going from the Rangers to the Yankees to the Mariners (in the questionable James Paxton deal). The right-handed pitching prospect has struggled to stay healthy at times but he reached triple-A in 2018 and should be one of the first starting pitchers recalled in 2019. He shows good control and an above-average fastball but he needs to polish his secondary offerings and keep the ball down. He looks like a future innings-eating No. 4 starter but there could be more here if he can improve his breaking ball and/or changeup.
The 2019 Sleeper: Jake Fraley, OF: The Mariners didn’t get enough in deals for top players James Paxton and Edwin Diaz but they did OK dealing Mike Zunino to the Rays. Fraley may end up as a (very good) fourth outfielder but he also has a solid change to develop into a starting outfielder. His speed and defensive give him good value and he showed some real improvement witht he bat during an injury-shortened 2018 in high-A ball. Fraley will likely move up to double-A in 2019 and should see the Majors by the end of the year if he continues to hit well.
The 2019 Lottery Ticket: Julio Rodriguez, OF: There are a few low-level minor league players that possess the ability to burst onto the scene like Vlad Guerrero Jr. and Fernando Tatis Jr. have in recent years. Wander Franco in Tampa Bay is one and Rodriguez could be another, although he’s not quite as advanced with the bat at this point. He has immense power potential but he doesn’t sell out for home runs and focuses on hitting the ball hard and using the whole field. He has a patient approach but also has swing-and-miss to his game due to a lack of experience rather than any major mechanical flaws. Rodriguez reportedly has solid makeup and is a hard worker, all things that can help a prospect maximize their tools.
Marc Hulet has been writing at FanGraphs since 2008. His work focuses on prospects and fantasy. Follow him on Twitter @marchulet.