SEATTLE -- In a season of unqualified success for the Mariners' Minor League system, two youngsters -- right-hander Zack Littell and slugging outfielder Tyler O'Neill -- have been selected as the Mariners prospects of the year by MLBPipeline.com.All seven of the Mariners' Minor League teams earned playoff berths in 2016
SEATTLE -- In a season of unqualified success for the Mariners' Minor League system, two youngsters -- right-hander Zack Littell and slugging outfielder Tyler O'Neill -- have been selected as the Mariners prospects of the year by MLBPipeline.com.
All seven of the Mariners' Minor League teams earned playoff berths in 2016 and Littell and O'Neill helped lead their teams' postseason runs.
Littell had a breakout season as a 20-year-old starter for Class A Clinton and Class A Advanced Bakersfield, combining for a 13-6 record and 2.66 ERA in 28 games, including 27 starts.
Littell, who turned 21 earlier this month and is the Mariners' No. 14 prospect, was an 11th-round Draft pick in 2013 out of Eastern Alamance High in Mebane, N.C.
After going 3-6 with a 3.91 ERA in 21 starts for Clinton in 2015, he opened the year with a 5-5 mark and 2.76 ERA in 16 starts for the same club, then pitched even better following a promotion to Bakersfield (8-1, 2.51 ERA) in 12 games (11 starts).
O'Neill, 21, had a big season as one of the youngest players in the Double-A Southern League when he hit .293/.374/.508 with 24 homers and 102 RBIs in 130 games for Jackson.
O'Neill, Seattle's No. 2 prospect and baseball's No. 59 overall prospect, is now headed to Arizona to compete in the Arizona Fall League.
"I'm just going to keep doing there how I ended," O'Neill said. "Just playing hard to the best of my ability and using everything I learned in Spring Training and throughout the season against the highest prospects in baseball. I want to come into Spring Training [next February] and make a statement there."
Both players adapted extremely well with the new Mariners regime's "control-the-zone" philosophy, a push to emphasize on-base percentages for offensive players and low walk rates for pitchers.
Littell had 84 strikeouts and 30 walks in 112 2/3 innings in 2015 for Clinton, but dramatically improved those numbers to 156 strikeouts with 34 walks in 165 2/3 innings this past season.
O'Neill enjoyed similar success on the offensive side. The youngster from Canada had 29 walks and 137 strikeouts in 449 plate appearances in 2015 with a .316 on-base percentage for Bakersfield, where he hit 32 home runs. He racked up 62 walks with 150 strikeouts in 575 plate appearances this year, helping hike his on-base percentage 58 points to .374.
"Obviously walking more was a big part of my development program," O'Neill said. "I kind of tuned it my own way, taking more pitches that were off the plate to get me into better counts to hit better pitches. That helped me a lot also. I took everything I learned this year and used it to the best of my ability."
Greg Johns has covered the Mariners since 1997, and for MLB.com since 2011. Follow him on Twitter [
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