10.) Luis Liberato – OF
Date of Birth: 12/18/95
Height/Weight: 6’1/175 pounds
Acquired: International Free Agency in 2012
We delve now into the top 10 of Mariner prospects starting with outfielder Luis Liberato. The adjustment to professional baseball has resulted in a bit of a learning curve for Liberato. While he did slash very well in Short Season A at .260/.341/.453, he struggled to replicate the success at both Class A and AA. There isn’t one attribute Liberato excels at necessarily, but he is pretty well rounded as a young player. He makes contact decently, has okay power, can field well and has a good arm and speed. He was signed as a center fielder but with Braden Bishop in Everett as well, Liberato shifted to left where he played well.
Having just turned 20, there’s still a lot to be seen with Luis Liberato. He’ll likely start the season at AA and try and improve on a rough patch of games last year. He still has a couple years of seasoning needed to reach his full potential, but could project as a solid corner outfielder who gets on base well and hits for decent average with average power. What is tremendously impressive about Liberato is that at such a young age he already has fantastic plate discipline which is usually rare amongst younger players.
9.) Drew Jackson – SS
Date of Birth: 7/28/93
Height/Weight: 6’2/ 200 pounds
Acquired: Drafted 5th round in 2015
The Mariners just may have found a gem in their fifth-round pick in 2015. Drew Jackson didn’t even emerge as any sort of a hitter until his senior year at Stanford, and now looks like he’s got elite tools to be a good hitter. Jackson slashed a ridiculous .358/.432/.447 while swiping an insane 47 bases in just 59 games. The interesting thing is that Jackson doesn’t have blazing speed, he’s just extremely athletic and a fantastic baserunner. His marvelous year earned him the Northwest League batting title along with league MVP.
Jackson doesn’t have much power, but also has a cannon for an arm and does a solid job at short. The biggest issue for Jackson may be the incredible depth that the Mariners have at shortstop. Current Mariner starter Ketel Marte just turned 22 in October, and looks like he may hold that job for a long time meaning Jackson will either have to prove he’s better or find himself a new position. Perhaps a switch to 2nd to succeed Robinson Cano? We shall see.
8. Austin Wilson – OF
Date of Birth: 2/7/92
Height/Weight: 6’4/249 pounds
Acquired: Drafted 2nd round in 2013
It’s been a tough start to a professional career for Austin Wilson. In his first year Wilson injured his Achillies and then needed elbow surgery not long after which has slowed his development as he’s attempted to recover from injury. He spent all of last year in Advanced A putting up okay numbers. His average wasn’t great but he got on base fairly well and still possesses a lot of raw power. His biggest weakness comes with the fact that he strikes out more than once every four at-bats, striking out 115 times last year in just 380 at-bats.
Wilson does a good job in the field and has a terrific arm playing all three outfield positions. He racked up 12 outfield assists last year while only committing four errors. Wilson doesn’t have great speed but he runs well enough to cover the outfield at a good rate. Wilson still has a lot of work to do before he reaches the MLB. He has to lower his strikeout rate, and that raw power has to become a lot more pure power. Wilson is already 23 so he shouldn’t have too much of a problem making adjustments and once he does that he should find himself in the bigs.
7.) Ian Miller – OF
Date of Birth: 2/21/92
Height/Weight: 6’0/175 pounds
Acquired: Drafted 14th round in 2013
Miller jumped up the Mariners ranks after a fairly impressive 2015 year. Seen as a career minor leaguer if that when drafted late, Miller has proven he’s a lot more than that. Splitting time between Advanced A and AA last year, Miller hit .267/.319/.330 with 25 XBH. His most impressive stat though was a stellar 50 stolen bases. His speed is easily the best part of his attributes, and it’s still getting better. Miller was caught 18 times last year, and has likely been working to lessen that number. He knows he lacks skill in other areas, namely power so having great speed can be a major asset towards making the bigs.
As mentioned Miller has no power whatsoever. In his three-year pro career, Miller has one home run, that coming in 2013 at Rookie ball. Fielding wise, he’s nothing flashy in the outfield despite his speed, but he’s also not a liability. His contact is improving and he’ll need it to if he wants to continue his climb. You can’t steal bases if you can’t get yourself on. Miller will most likely start the year with AA Jackson, but has a great chance to move up quickly to Tacoma if he continues to hit the ball well.
6. Tyler O’Neill – OF
Date of Birth: 6/22/95
Height/Weight: 5’11/210 pounds
Acquired: Drafted 3rd round in 2013
A lot of players on this list for the Mariners are good defenders with solid contact ability and minimal power. Tyler O’Neill on the other hand is a below average defender, with okay contact and major power. The big left fielder smacked 32 dingers last year and knocked in 87 runs while hitting .260/.316/.558 which isn’t bad for a youngster with so much raw power. He also swiped 16 bases, again not bad for a power guy. What O’Neill’s biggest weakness comes in is his strikeout numbers. In 407 at-bats, O’Neill struckout 137 times, which isn’t so surprising for a 20-year-old power hitter.
O’Neill still has to do some work before he’ll be big league ready. The power is enticing, but he’s got to make sure it can translate into advanced pitching. Like many players on this list, O’Neill will likely start the season in AA next year, and the Mariners will be keeping close tabs to see whether or not he can continue to hit the ball deep and whether or not he can start getting better contact and lessen his strikeout numbers. If those two things happen, O’Neill could make his way to Seattle sooner rather than later.