Mariners Prospect Primer: Lewis on the mend

Some players are on the verge of stardom, others are entering a crucial phase of their development and still others are getting their first tastes of full-season ball. With the 2017 season approaching, MiLB.com takes a look at the most intriguing prospects from each MLB organization.
Shining star: Kyle Lewis , OF
An unheralded high school recruit out of Georgia in 2013, Lewis was largely ignored by SEC schools and landed at Mercer, where he ended up winning the 2016 USA Baseball Golden Spikes Award. The Mariners made him the 11th overall pick in last year's Draft but Lewis started slow, batting .175/.283/.250 in his first 10 games with Class A Short Season Everett.

The 6-foot-4, 210-pound outfielder proceeded to go on a tear over the next three weeks, posting a .364/.438/.675 slash line with three homers, 25 RBIs, 20 runs scored and two stolen bases over his next 20 games. But a home-plate collision on July 19 resulted in a torn ACL for the 21-year-old, who's been in recovery mode ever since. As much as the injury could be viewed as a setback, it also confirmed to the Mariners that the player they drafted was exactly who they thought he was.
"I would say for Kyle that everything was as advertised coming out of the Draft, and based on our amateur scouting reports it all showed up in Everett," Mariners director of player development Andy McKay said. "Most importantly, once the injury set in, the character has surfaced as to what kind of guy he is -- he's handled the injury as well as he could. We couldn't be more excited about what we have."
In November, Lewis said he was "right on track" in his recovery. The organization is aiming to have its No. 1 prospect back toward the end of the first half, and Mariners fans and the team are hoping he hits the ground running in advance of a big rise through the organizational ranks.
Loudest tool: Tyler O'Neill, OF
Coming off a California League-leading 32 home runs in his age-20 season with Class A Advanced Bakersfield in 2015, O'Neill had an even more impressive campaign with Double-A Jackson in 2016. While his 24 long balls with the Generals didn't match his total from the prior year, they ranked second on the circuit behind Mobile's Kevin Cron, and O'Neill displayed an improved approach at the plate, batting .293/.374/.508 in 130 games and walking 62 times -- which matched his career total in 195 contests entering the season.
"Anybody who's been around Tyler will mention some ball he's hit that's the farthest ball they've ever seen hit," McKay said. "Obviously the power has always been there, and the ability to control the strike zone has really helped his game. You don't have to look far past what he did in the Southern League at the age he did to see the talent he has. He'll start in the PCL at age 22 and showed well at camp this year."
Not only did O'Neill increase his walks last season, he also continued to lower his strikeout rate -- from 32.9 percent in 2014 to 30.5 percent in 2015 and 26.1 last season. Combining those incremental improvements with a move to the hitter-friendly Pacific Coast League, O'Neill could find himself back in the 30-homer club in 2017. Although if he continues his trajectory with the Rainiers, he may not stay in the Minors long.
Major League-ready: Mitch Haniger, OF
Acquired from Arizona in a five-player trade in November, the 26-year-old Haniger is currently the heavy favorite to start the season patrolling right field at Safeco Field. His 2016 campaign showed he has little left to prove in the Minors as Haniger hit .341/.428/.670 in 74 games after a June promotion to Triple-A Reno. His Major League numbers -- .229/.309/.404, five homers, 17 RBIs in 34 games -- pale in comparison to that PCL-inflated line, but he wouldn't be the first prospect to struggle during a cup of coffee and then produce the following season.
"We picked up [Jean] Segura, which was a big addition to our club, but Mitch was a guy we highly coveted based on his performance in 2016 across three levels of pro baseball and after digging into his makeup," McKay said. "We think we have a performer with a real tool set and great makeup, and everything so far that we've seen has shown us we were right, so we couldn't be more excited to have acquired Mitch."
Steamer's projections like Haniger as nearly a two-win player who should be able to hold his own with the bat this season. His 60-grade arm and solid athleticism should make him a positive asset defensively even if the bat is slow to come around, but all indications point in the opposite direction after an impressive Spring Training. The No. 38 overall pick in the 2012 Draft was hitting .400/.443/.677 with two homers, 10 RBIs and three steals in 70 plate appearances this spring and looks ready to build on his sleeper buzz in Seattle.
At the crossroads: D.J. Peterson, 1B
A monster 2014 campaign at age 22 had Peterson's prospect stock skyrocketing, but injuries and inconsistency have stalled his development. After hitting .297/.360/.552 with 31 homers and 111 RBIs at Class A Advanced and Double-A that year, the Mariners' 2013 first-round pick started 2015 slowly and never got untracked, finishing with a .223/.287/.344 line, seven homers and 44 RBIs in 97 games before an Achilles' injury ended his season in August.
Back in Jackson for a third go-round in 2016, Peterson bounced back with a .271/.340/.466 line, 11 long balls and 43 RBIs in 73 games before a promotion to Tacoma, where he finished at .253/.307/.438 with eight homers and 35 RBIs in 46 games. Another August injury ended his season early; this time the culprit was a fractured finger.
"D.J. made enormous strides last year starting off in Double-A and really got things on track in Triple-A," McKay said. "Then he cooled off a bit at the end, and he's definitely at that point of his career -- he'll start in Triple-A. With all the work he's put in, he's now got every opportunity he's always wanted and is one phone call away."
Earning a 40-man roster spot was a big accomplishment for the 25-year-old first baseman, who is no longer viewed as an option at the hot corner -- he's played 38 games there over the past two seasons after logging 90 in 2014. With only Danny Valencia and Dan Vogelbach ahead of him on the depth chart now, 2016 could be a make-or-break year for the team's 11th-ranked prospect. A hot start could land him in Majors by the summer, but another slow campaign could stall his development once more.
Full-season debutant: Joe Rizzo, 3B
Rizzo enjoyed a promising first two weeks with the Rookie-level AZL Mariners, sitting on a .348/.400/.565 batting line with two homers, eight RBIs and 10 runs scored after a 3-for-5 performance on July 4. He finished with a solid .291/.355/.392 slash line, using his plus bat speed and plate discipline to effectively navigate through his first half-season of pro ball.
"[Joe is] another guy our scouts evaluated as being one of, if not the top high school bat in the country, and he's exactly what we thought we were getting," McKay said. "He's definitely an advanced hitter for his age -- he'll continue to work and stabilize himself as a third baseman, and he's definitely a bat you can't help but get excited about when you watch [him] play."
Seattle's second-round pick in the 2016 Draft, Rizzo has been praised by scouts for his batting eye along with his feel at the plate but were torn on his long-term position. The Mariners remain committed to developing the 5-foot-9, 194-pound New Jersey native as a third baseman, and team officials have consistently praised his makeup -- a trait he shares with many of the system's top prospects.

Others to keep an eye on: No. 3 prospect Nick Neidert impressed in his full-season debut for Class A Clinton with a 2.57 ERA and 13 walks in 91 innings at age 19, a number that fails to accurately describe his polish. "This is a very advanced high school signing who can really execute a pitch and command a fastball and competes as well as anybody," McKay said. "When you get high school players who come in with college maturity it's rare, and he definitely has that." ... While O'Neill is the system's big-name prospect with a loud tool, Thyago Vieira and his triple-digit heat tend to fly under the radar. The 23-year-old right-hander consistently works in the upper-90s and has touched 102 mph with his 80-grade fastball. The 2010 international signing out of Brazil needs to continue refining his command, but as a member of Seattle's 40-man roster, he's a sneaky candidate to be part of the Mariners' bullpen by the end of the season and profiles as a future closer. ... The aforementioned Vogelbach, ranked No. 10 in the organization after being acquired from the Cubs last season, was surprisingly optioned to Triple-A Tacoma on March 23 but still projects as a contributor to the big league club this season. A rough end to Spring Training -- Vogelbach finished with two hits and 10 strikeouts in his final 22 spring at-bats -- likely sealed his fate, but Seattle took the same approach with Mike Zunino and James Paxton last season, only to recall both players in June.