Mariners May Turn to Peterson at First Base

The Mariners have quickly built a young competitive roster which should be a favorite to attain a playoff birth this season. With Kyle Seager, Robinson Cano, Brad Miller, and Mike Zunino all entrenched at their respective positions, only first base can be considered a question mark in the Seattle infield. Although incumbent Logan Morrison returns as the likely favorite for the position, he may face some stiff competition from high-rated prospect, D.J. Peterson.

The 12^th overall pick in the 2013 MLB Draft, the 6-foot-1, 190 pound Peterson immediately became one of Seattle’s top prospects. As a right-handed hitter with the power potential to hit 30+ home runs in a 162 game season, his future could reside in the middle of Seattle’s lineup. The key for Peterson is just how quickly that potential comes to fruition.

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He’ll finally get his chance to show that he belongs as he joins the Mariners in Spring Training. A major part of that demonstration will come on the defensive side of the field. With Kyle Seager locked in at third base for the majority of the next decade and Nelson Cruz signing in the offseason as the full-time DH, Peterson should get most of his playing time at first as the Mariners look for a way to get his bat into the lineup. As a third baseman for the majority of his career in the minors and in college, Peterson will have to show that he can shift to the other side in order to reach the majors at an expedited rate.

Although he’s only 23, he’s taken a veteran approach to that possibility, recently saying “Whatever it takes to get me to the big leagues is what I’m going to do,” Peterson said. “If Jack Zduriencik called me and said, ‘You need to catch,’ I would be catching” he told MLB.com. He’ll need that mindset after playing only 19 games at first base in 2014 and only one in 2013.

Despite his inexperience at first, his hitting tools will translate no matter where he plays on the diamond. After briefly struggling in High-A Desert in 2014, he bounced back to post a .326 batting average, .381 on-base percentage, and gaudy .289 Isolated Power across 65 games.

Those numbers were even more impressive considering his 2013 season was cut short when he was hit in the face with a pitch. After undergoing surgery on his broken jaw, he wasn’t allowed t to resume baseball activities for three months, which delayed his first invitation to major league camp until this year.

The extra time in the minors may have proved helpful as he cut down his strikeout rate (20.6%) and increased his walk rate (8.9%) after being promoted to Double-A. His others numbers, most notably his slugging percentage dipped (from .615 to .473), but his 13 home runs in 58 games was still on par with what was expected, leading to an Arizona Fall League Stars Game appearance.

Now bright-eyed and excited to be in Spring Training, Peterson has an excellent chance to make the jump from Double-A to the majors. With Justin Smoak now in Toronto after being placed on waivers, Peterson’s main competition will come from projected starting first baseman, Logan Morrison.

Seattle Mariners’ First Baseman, Logan Morrison

Morrison is coming off a less than stellar season where he missed 80 games due to numerous injuries and hasn’t played in 100 games in any of the last three years. With a batting average below .250 in two out of the last three years, a terrible walk percentage in 2014, and a negative defensive rating since 2012, Morrison’s hold on the starting spot is tenuous at best.

With a strong showing at Spring Training, Peterson could prove he’s the better option going forward, even with some rookie struggles throughout the season. His case is aided by Zduriencik’s vocal support. “He’ll roll into Spring Training, and we’ll see,” Zduriencik said. “He’s got a gift to hit the baseball, and that will play for us at some point,” reports MLB.com.

With average starting first basemen sporting around a .340 weighted on base average during the 2014 season, Morrison only posting a .324 wOBA in 2014, and Peterson earning a .365 wOBA during his time in Double-A, the numbers may favor the risk that comes with Peterson’s inexperience.

If he can prove he can handle the defensive responsibilities of first base on a consistent basis and validate his reputation as a hitter who can pile up extra base hits, there’s no reason that Peterson shouldn’t be the Mariner’s starting first baseman on Opening Day.

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