SEATTLE -- Julio Rodríguez will make his big league debut on Friday, signaling another significant milestone for a farm system that ranks No. 2 in baseball as it prepares to graduate one of its homegrown talents.

J-Rod comes with much hype and fanfare as MLB Pipeline's No. 3 overall prospect, particularly given that he's been arguably the most prominent international prospect acquired by the Mariners since president of baseball operations Jerry Dipoto took over in 2015.

The 21-year-old Dominican Republic native joins a slew of stars who have come through the club's pipeline over the years. Some have lived up to their hype, while others haven’t quite matched their scouting reports.

Now that Rodríguez is on the cusp, we thought it would be the perfect time to take a look at some of Seattle's most touted prospects of all time, examine why those players carried such a pedigree and how they performed in the big leagues.

Here are the 10 most touted prospects in Mariners history:

1. Ken Griffey Jr.
Why he was hyped: Ken Griffey Jr. was the son of a three-time All-Star and .300 hitter to that point, had all the tools coming out of Moeller High School in Cincinnati and backed that potential by depositing home runs into the upper decks of the Kingdome just days after signing -- all at the ripe age of 17. Griffey surged through the Minors, hitting .320/.427/.576 (1.003 OPS) with 27 homers over a year and a half, needing just 462 at-bats to convince management that he was ready to be a permanent big leaguer at age 19 in 1989.

How he panned out: No player in the game’s 150-plus-year history has lived up to his preconceived billing like The Kid. Griffey became the first No. 1 overall Draft pick to be selected to the Hall of Fame, and his 99.3% first-ballot vote was the highest of any player selected to Cooperstown at the time of his enshrinement in 2016. He was an All-Star in each of his first 11 seasons in Seattle other than his rookie year, he won the 1997 American League MVP Award and blossomed into arguably the greatest player of his generation. Griffey’s legacy continues, as he’s been a special consultant to the Mariners since retiring in ‘10, and in ‘21, he was hired as a senior consultant to Commissioner Rob Manfred.

2. Alex Rodriguez
Why he was hyped: Like Griffey, Alex Rodriguez was a No. 1 overall Draft pick and oozed with so much potential that the Mariners signed him to a three-year, $1.3 million deal with a $1 million signing bonus. By Spring Training the following year, in 1994, Rodriguez was widely considered the game’s top prospect at age 18. He wound up debuting that season, after playing in just 82 Minor League games and just 13 months removed from his high school graduation.

How he panned out: Though A-Rod showed he needed more Minor League development from 1994-95, he hit his stride in ’96, winning the AL batting title with a .358 average -- the third-youngest such champion in baseball history behind only Al Kaline and Ty Cobb -- with 36 homers and 123 RBIs, finishing runner up in the AL MVP Award voting. That was only the start; Rodriguez hit .309/.374/.561 with 189 homers and 595 RBIs, and despite playing just seven seasons in Seattle, his 38.1 wins above replacement are sixth-most in franchise history.

3. Félix Hernández
Why he was hyped: Félix Hernández was called “The King” by local blogs well before making his Major League debut. He signed as an international free agent in 2002, as soon as he became eligible to after his 16th birthday, and he quickly soared through Seattle’s farm system, striking out nearly 30% of the batters he faced and compiling a 2.58 ERA in the Minors. Most scouting outlets ranked him as the best pitching prospect at the time, along with Zack Greinke and Edwin Jackson.

How he panned out: Hernández put together a fringe Hall-of-Fame-worthy career over a whopping 15 seasons in Seattle. He wowed in his debut season in 2005, threw the only perfect game in Mariners history (which remains the most recent in MLB history), never suffered a season-ending arm injury, and despite his team’s shortcomings, he won the 2010 AL Cy Young Award, ushering a modern thinking among voters that put more of a premium on individual numbers. Hernández went 13-12 that year, but he faced more batters (1,001) than any pitcher and had MLB's best ERA (2.27). His 50.1 bWAR are fourth-most in Mariners history.

4. Julio Rodríguez
Why he was hyped: Julio Rodríguez had an impressive Spring Training, an even stronger showing in '21, and by '22, he put together the best camp of any Seattle player. For being just 21 years old, the right-handed-hitting outfielder has shown prodigious power that rivals Giancarlo Stanton, Aaron Judge and Nelson Cruz, with exit-velocity readings in the 115 mph range. He already looked and sounded every bit like a big leaguer well before he took the stage, and he's emerged as a fan favorite.

How he panned out: TBD. Rodríguez has excelled at every step of his Minor League development, but now comes the big test -- specifically the challenge of facing, and beating, big league pitching on a nightly basis.

5. Jarred Kelenic
Why he was hyped: Kelenic was the headline return in the Robinson Canó/Edwin Díaz blockbuster with the Mets that jumpstarted the first true Mariners rebuild after the 2018 season. Kelenic skyrocketed up prospect charts after hitting .291/.364/.540 with 23 homers in his first full pro season, ’19. His floor has been as high as a consistent 20-homer All-Star, and his ceiling suggests he might contend for AL batting titles with the potential to hit 30 homers.

How he panned out: TBD. Kelenic had a challenging rookie season, but he did show signs of improvement each month, specifically after finding more mental balance following a Minor League demotion after his first few weeks in The Show. At every level, he's had an advanced hitting approach, with all signs suggesting he will excel in the Majors.

6. Dustin Ackley
Why he was hyped: Dustin Ackley was drafted with the No. 2 overall pick in 2009 out of North Carolina, touted by some as the best college hitter in history -- so much so that first-year general manager Jack Zduriencik shelled out a $7.5 million contract 15 minutes before the deadline to sign that year’s picks. The only three-time All-American in the Tar Heels’ rich baseball history, Ackley hit .410 at UNC and helped the team reach the College World Series. Stephen Strasburg was that year’s Draft star, but Ackley was a very close second.

How he panned out: Billed a can’t-miss pick, Ackley went on to have a solid rookie season, but that was his only highlight in Seattle. Big league pitchers quickly adjusted to him and his strikeout number soared. He wound up bouncing around the field defensively, then out of Seattle altogether in a trade in 2015. The biggest blip for the Mariners here was that by selecting Ackley, they passed on Mike Trout.

7. Ryan Anderson
Why he was hyped: The 6-foot-10 first-round pick in 1997 was dubbed The Little Unit and drew comparisons to Randy Johnson -- lofty praise for any young player. But Ryan Anderson looked the part as a lanky lefty with gas that had Mariners fans drooling over the potential of a tandem with the eventual Hall of Famer. Anderson was widely considered the Mariners’ best prospect for a five-year stretch, also ranking among the Minors’ best in that span. Anderson backed it with 12.3 strikeouts per nine innings as an 18-year-old, behind only A.J. Burnett among starters.

How he panned out: Shoulder injuries derailed the lefty’s potential and sidelined him from the 2001-04 seasons, which made him one of the biggest Draft disappointments in franchise history. Anderson wound up becoming a sous chef in Japan after his playing days.

8. Mike Zunino
Why he was hyped: Mike Zunino wowed big league evaluators coming out of the University of Florida, prompting Zduriencik to select the slugging backstop with the No. 3 overall pick in 2012. Catchers with the power tool Zunino possessed -- he hit 38 homers in his final two years in college and 24 more in the Minors before debuting in ‘13 -- are a rare commodity.

How he panned out: The uber-athletic Zunino blossomed into one of the best defensive backstops in the big leagues, and while his bat showed occasional pop (95 homers in parts of six seasons in Seattle), it never quite caught up to his glove. He was dealt to Tampa Bay in the first significant trade of the Jerry Dipoto stepback of 2018.

9. Adam Jones
Why he was hyped: Adam Jones drew praise for his versatility -- he was drafted in the first round as a pitcher and shortstop. Yet he wound up converting to the outfield. Jones opted to sign with the Mariners instead of playing at San Diego State for Tony Gwynn, and he played for the 2006-07 Triple-A Tacoma teams that featured Major Leaguers such as Asdrubal Cabrera and Shin-Soo Choo. He was Seattle’s Minor League Player of the Year in ’07 after hitting .314 with 25 homers and 84 RBIs for Tacoma.

How he panned out: Jones became a five-time All-Star, but not until after he was traded by Seattle to Baltimore in 2008 as the key piece in the trade for Erik Bedard, who the Mariners touted with ace potential. It wound up being one of the more regrettable trades for then general manager Bill Bavasi, who was fired four months later.

10. Danny Hultzen
Why he was hyped: Danny Hultzen was the ACC Pitcher of the Year in 2010 at the University of Virginia, then he one-upped himself by earning the John Olerud Award in ’11 as college baseball’s best two-way player. That billing was more than enough incentive for the Mariners to select the left-hander with the No. 2 overall pick in ’11, behind only Gerrit Cole. Hultzen continued to exhibit hype in the Minors, jumping as high as MLB Pipeline’s No. 16 overall prospect.

How he panned out: No pitcher with as much prominence in the Mariners’ farm system suffered as much of a downfall as Hultzen, who battled multiple shoulder injuries that required surgery. He wouldn’t pitch in the Majors until 2019 with the Cubs, and even then, it was only six quick outings.