Mariners Prospect Primer: Jackson in action

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 2015 season approaching, MiLB.com takes a look at the most intriguing prospects from each MLB organization.

Shining star: Alex Jackson, OF

Not to be outlandish, but it's tough to look at Jackson's profile and not think of Bryce Harper. OK, one was the first overall pick back in 2010 and the other was taken sixth last June. But both were hyped prospects who have made the move from high-school catcher to professional outfielder in order to play up their special bats. Jackson has plenty to prove to reach Harper's level -- he's MLB.com's No. 29 overall prospect after only 82 at-bats in the Arizona League -- but the tools are there.

The 19-year-old right-handed slugger has already impressed his organization and scouts with plus hitting and power tools, a lethal combination that could make him one of the best hitters in Class A ball this season. He showed it off some with a home run in a Major League Spring Training game against the Rangers on March 20.

"He's really impressed our staff already," said Jack Mosimann, an assistant in the Mariners player development department. "He's a very mature person and composed for his age, given he's just 19 years old. At the Winter Meetings, he was named [Baseball America] High School Player of the Year because of his talents on the field. Off it, he's a class act, very courteous. He has the heart, instincts and character to be a good player here for a long time."

Back and healthy: Danny Hultzen, LHP

Speaking of high-profile first-rounders, Hultzen fell off the prospect landscape in the last year after shoulder issues that plagued him in 2013 forced him to get season-losing surgery in 2014. Mariners fans are much less likely to forget the 2011 No. 2 overall pick, and in 2015, they'll finally get to see the 25-year-old left-hander return to a Minor League mound.

Seattle will be predictably cautious with their now-No. 25 prospect. The organization is still planning out an innings limit and a starting point for Hultzen, although Mariners manager Lloyd McClendon indicated it's likely to be in warm weather, which could mean anywhere between Triple-A Tacoma (which opens in El Paso and Albuquerque) or extended spring training, where he can be better monitored.

In any event, the focus will be on establishing any kind of optimism for Hultzen after a year-plus away from the game. A scoreless inning against the Rockies on March -- Hultzen's first official outing of any kind since Sept. 1, 2013 -- was a monumental and symbolic first step toward achieving that. 

"Danny's healthy right now, and we're happy with the progress he's made this spring and through the whole rehab process," Mosimann said. "He challenged himself this offseason and through rehab to overcome the circumstances with his shoulder, and when he had that first time out at a big league game after all, it made our entire organization proud that he is part of this organization."

Major League-ready: Carson Smith, RHP

When you start a sentence like "Carson Smith looks ..." you'd probably end it with "different" or "unorthodox" or maybe even "wacky" based on his three-quarters delivery that looks more like he's shot-putting the ball than pitching it. All the same, he looked good last year at Triple-A Tacoma, where the 6-foot-6 right-hander, who can sit in the mid-90s with his fastball and has an above-average slider, had a 2.93 ERA and a 1.33 WHIP with 45 strikeouts and only 13 walks in 43 innings. The Mariners thought enough of their No. 10 prospect to bring him up and use him in September while they chased the playoffs, and he starred in the bigs, fanning 10 while allowing just two hits and three walks in nine scoreless frames.

Mariners relievers had a Majors-best 2.60 ERA in 2014, and not too many changes are expected for the coming season. If Smith does head back to Triple-A Tacoma, he would be perhaps the first promoted if one of Seattle's many right-handed relievers went down to injury or struggled in some big way. Don't be surprised if a setup role isn't much further beyond. 

Breakout prospect: Jordy Lara, 1B/OF

It's tough to call a reigning Mariners Minor League Player of the Year who hit .337 with 26 homers last season the potential breakout player of 2015, but Lara is only ranked as the No. 16 prospect in the M's system. A big reason for that is he did the majority of his damage at Class A Advanced High Desert, where all offensive production can be taken with a mountain of salt. (Note: the Mariners' Class A Advanced affiliate has moved to Bakersfield for the upcoming season.)

But the right-handed slugger did perform well in a 33-game sample at Double-A Jackson (.286/.326/.492) and did the same in a 15-game spell (.298/.441/.553, three homers) in the Dominican Winter League. Asking for a repeat of 2014 is out of the question, but if Lara can impress over a longer span in the higher levels in 2015 -- and especially if he can continue to show an increased ability to take walks -- he'd answer a lot of remaining questions and would send his stock surging over the summer.

"We're looking for Jordy to provide us more of that continued consistency he showed us all last year," Mosimann said. "He obviously excelled at High Desert. But he did well at Jackson too, and comparing the two, those are just completely different ballparks. We want to get more at-bats under him and the proper seasoning before he advances up to Triple-A."

Loudest tool: D.J. Peterson, 3B/1B, power

There may be a day when Jackson has power equal to or even greater than that of Peterson. But in terms of present tools, the nod goes firmly in the latter's direction. That shouldn't be a surprise after the 23-year-old right-handed slugger finished tied for seventh in the Minor Leagues with 31 homers last season between Double-A Jackson and Class A Advanced High Desert. What's more, his .255 isolated slugging percentage (ISO) ranked eighth among Top-100 prospects in 2014, between breakout Dodgers stars Joc Pederson (.279) and Corey Seager (.253). 

Peterson's power didn't come as a surprise to the Mariners, who took him 12th overall in the 2013 Draft out of the University of New Mexico.

The unknowns, however, come down to his defensive positioning in the coming year. The Mariners inked third baseman Kyle Seager to a seven-year extension this offseason, blocking Peterson at his initial position for years to come. Peterson got 18 starts at first base in 2014, and without a long-term Major League solution at the position, that looks like his clearer road to Seattle. For now, he'll likely begin the 2015 season back in Double-A, where he hit .261/.335/.473 with 13 homers in 58 games last season, set for lift off once more.

"D.J.'s really challenged himself to grasp both positions, and right now, he's been doing a very good job of that," said Mosimann. "His bat's there. There's no real question about that. He's still working on the things he needs to work on defensively, but all in all, it's just a matter of D.J. getting plate appearances and reps in the field."

More to keep an eye on: Patrick Kivlehan is (literally) in a similar position to Peterson in that his natural position is third base, but he's considered to be blocked long term at the hot corner. The Mariners' No. 4 prospect also has experience at first base and the outfield, leading Mosimann to say he is "diversifying his value." No matter what positioning, a Jackson lineup that might include Peterson, Lara and Kivlehan could be deadly in the Southern League. ... Gareth Morgan, the 74th overall pick in 2014, hit just .146 and struck out in 41 percent of his at-bats during his 45-game stay in the Arizona League, but the Mariners aren't concerned with the outfielder, whose power earned a 60 grade from MLB.com this offseason, heading into his first full pro summer. "We see large things in Gareth," Mosimann said. ... Add Gabby Guerrero, nephew of Vladimir, to the list of names under the heading, "What can he do outside of High Desert?" after the right-hander hit .307/.347/.467 with 18 homers in the Cal League last season. One thing we know for sure: He's got his uncle's arm. The right fielder had 10 outfield assists in 2014 and earned a 65 grade on his arm from MLB.com.