SEATTLE -- Jerry Dipoto is well aware that Baseball America recently ranked the Mariners' farm system as the worst in the Major Leagues. But while Seattle's third-year general manager acknowledges that trades, injuries and promotions to the Major League roster have slimmed Seattle's prospect list, he offers sharp rebuttal to any notion that the club's development system hasn't been robust and productive.
Dipoto frequently notes that the Mariners have gone from one of the oldest rosters in the Majors to one of the youngest over the past two years, largely by trading prospects for young, cost-effective Major League players. Those younger players -- like Mitch Haniger, Jean Segura, Ben Gamel, Ryon Healy and Marco Gonzales -- are under team control for another five to six years and will allow the franchise to restock behind them.
Dipoto and Andy McKay, the club's director of player development, see those additions as direct products of the farm system, even if they weren't drafted by Seattle.

"What I know is the players in our program are highly coveted by other organizations," McKay said. "We are producing players other teams want. I look at that as a real measure of what we're doing. Our players know how to win baseball games and control the strike zone, and they've done that as well as any organization in professional baseball, and we're proud of that. I think that's a real good measure."
Other quality youngsters like catcher Mike Zunino, relievers Edwin Diaz and Dan Altavilla, and starting candidate Andrew Moore have been drafted and developed. And Dipoto and McKay insist there are plenty of valuable prospects still in the system.
"I respect Baseball America," Dipoto said. "But we are a little more bullish on our group than they are, to be frank."

The Mariners' farm system was ranked 28th by Baseball America two years ago, but still produced a considerable impact on the Major League roster in 2017.
"You're not going to make too many advances in prospect rankings when you graduate 475 innings pitched in the big leagues, which is what our rookies did last year," Dipoto said. "Or 250 games pitched, which is what our rookies did last year, or 1,522 plate appearances. That is the most innings pitched by rookies, the most games pitched by rookies, and the second-most plate appearances taken by rookies in the American League. It's the most in each one of those categories in the history of the Mariners.
"We transitioned a lot of young players to the big leagues and they're no longer eligible for prospect lists. That doesn't make them less than good young players. Guys like Marco Gonzales, Mitch Haniger, Ben Gamel and Andrew Moore, who otherwise would have been on such a list, are no longer eligible. So, look at all the details, and I'm very comfortable with what we've done organizationally and how we set up."
Going forward, several players widely recognized as Seattle's premier prospects are coming off injuries. Outfield Kyle Lewis, the club's No. 1 prospect per MLB Pipeline, played just 55 games last season after missing a year following reconstructive knee surgery.
No. 2 prospect Evan White was last June's first-round Draft pick, but played just 14 games before being sidelined by a strained quadricep. No. 3 prospect Sam Carlson pitched just two games after being drafted as a high school senior out of Minnesota.

No. 5 prospect Julio Rodriguez is a 17-year-old outfielder out of the Dominican Republic who is yet to play a professional game in the Mariners' system.
Clearly the rash of trades and promotions have thinned Seattle's remaining crop of eligible prospects, which is what Baseball America and others are now rating.
"Now it's on us moving forward," Dipoto said. "I can't criticize them for choosing to put us in that position. All I can do is take the challenge and we as an organization will try to make that better.
"But our main priority here is teaching our players how to win, teaching our players how to progress, and that when they get to the big leagues they're ready to take that final step. People, process and programs are going very well here. We're excited about the team we have on the field for 2018. We know there are some questions that we're going to have to answer along the way, but that's part of the fun of baseball."
Prospect ratings certainly aren't foolproof. The Mariners had one of the higher-rated farm systems several years ago, but few of their top-rated players panned out. McKay noted that prospect rankings don't always mesh with how players' careers play out, citing relievers Art Warren and Matt Festa as two youngsters not even on anyone's radar last year who are now rising prospects invited to the Mariners' Major League camp next month.
"We have plenty of players in our system that are not only going to impact the Major Leagues, they're going to impact it in a big way," McKay said.