ESPN says Mariners have 28th-ranked farm system in MLB

Alex Jackson’s 2015 season was a serious step back. The club’s first pick from the 2014 MLB first-year player draft (No. 6 overall) batted .157 with no homers and 13 RBIs in 28 games for Class-A Clinton before being demoted to Class A short-season Everett. The 19-year-old outfielder improved for the Aquasox, posting an .832 OPS in 48 games, but he still has a long way to go before he fulfills the expectations that came with being one of the most touted right-handed hitters in his draft class. (Otto Greule Jr., Getty Images) less Alex Jackson’s 2015 season was a serious step back. The club’s first pick from the 2014 MLB first-year player draft (No. 6 overall) batted .157 with no homers and 13 RBIs in 28 games for Class-A Clinton ... more Image 1 of / 27 Caption Close ESPN says Mariners have 28th-ranked farm system in MLB 1 / 27 Back to Gallery

After spending his first offseason with the Mariners overhauling the major-league roster, general manager Jerry Dipoto still has work left in terms of rebuilding a depleted farm system.

ESPN analyst Keith Law this week ranked the Mariners' minor-league system 28th in baseball, down from 21st last year.

A big reason for the drop-off was a down season from right fielder Alex Jackson.

The 20-year-old was the Mariners' first-round pick (sixth overall) in the 2014 MLB draft. Last season, he batted a combined .207 with 17 doubles, eight homers and 38 RBIs in 76 games combined between Short-A Everett and Class-A Clinton. That dropped Jackson from the 59th-rated prospect in 2015 to 95th this year. He is the only Mariners prospect in Law's "Top 100."

Here's an excerpt from Law's story. You need an ESPN Insider subscription to read it.

Their best prospect took a big step back in 2015; their top pitching prospect has huge upside but hasn't performed and has major makeup questions; and their draft was my least favorite of all 30 in 2015. New GM Jerry Dipoto has the unenviable task of keeping the big league club competitive while trying to restock the fallen system.

The regression of D.J. Peterson almost certainly played a role in the low ranking. Peterson, the Mariners first-round pick in the 2013 MLB draft (12th overall), spent most of last season with Double-A Jackson, where he batted .223 with seven homers and 44 RBIs in 93 games. Despite getting off to a slow start, then-general manager Jack Zduriencik opted to move Peterson to Triple-A Tacoma. But the first baseman played in only four games before hurting his Achilles and missing the rest of the season.

Before completely eviscerating Zduriencik for questionable draft choices and the system's poor player development (probably fair), it's important to note that shortstop Ketel Marte showed he was big-league ready last season after making his was through the system. Third baseman Kyle Seager has turned out alright, winning a Gold Glove and making the AL All-Star team in 2014. He was a third-round pick in the 2009 MLB draft before making his way through the system.

The point: there are a few success stories outside of the failures of catcher Mike Zunino, left fielder Dustin Ackley and many others.

If Dipoto is to serve as this organization's savior, he'll need to improve on his work as GM for the Los Angeles Angels of Anaheim over three-and-a-half seasons. Law ranks the Angels' farm system 30th -- dead last.

Enjoy the gallery above to see the top 18 Mariners prospects.

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