PEORIA, Ariz. -- The Mariners¡¯ success of turning unheralded relievers in Spring Training into legitimate contributors has been one of the club¡¯s greatest success stories of recent memory, which begs to question: Who¡¯s the next Paul Sewald, Justin Topa or Gabe Speier entering 2024?

Manager Scott Servais even coined a nickname for the army of arms that arrived this week -- the ¡°Steckenrider Bucket,¡± a nod to former Mariners reliever Drew Steckenrider, a non-roster invite in ¡®21 who became a key piece to that year¡¯s ¡®pen.

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The criteria is straightforward: Players with MLB experience elsewhere who have had limited success but possess a plus pitch, or more, that the Mariners believe can unlock more potential.

¡°Just based on how their career has gone, what the stuff profiles to be, how can they fit on our team? Things like that,¡± Servais said. ¡°I think we've got four or five of those guys in that bucket.¡±

Here¡¯s a look at this year¡¯s crop (in alphabetical order):

RHP Cody Bolton
Previous team(s): Pirates
The stuff: 3 mph jump on sinker

Bolton made his MLB debut last year, after five seasons in the Minors, posting a 6.33 ERA with 15 walks in 16 outings. Most of the damage against him was on his four-seam fastball, which opposing hitters had a .378 batting average against. He also throws a two-seamer/sinker, per Brooks Baseball (which tracks Minors data) and saw a notable uptick in velocity. Two-seamers are all the rave in Seattle, so maybe there¡¯s something to work with.

RHP Ty Buttrey
Previous team(s): Angels, Astros
The stuff: 95th percentile in FB velo in ¡®19

The Mariners know him well from his 2019 season with the Angels, when his 1.5 wins above replacement, per FanGraphs, were tied for MLB¡¯s 15th best among relievers. He threw as hard as anyone back then, too, before tumbling out of the organization, leaving baseball all together in ¡®21, then pitching in the Minors for Houston from ¡®22-23. It¡¯s been a long time since he was elite, but there¡¯s no risk in giving him a look.

RHP Jackson Kowar
Previous team(s): Royals, Braves
The stuff: 96.9 mph fastball, 32.4% slider whiff rate in ¡®23

In 39 outings with the Royals from 2021-23, Kowar had a 9.12 ERA, 49 ERA+ (league average is 100), 2.095 WHIP and a 13.7% walk rate. But the Mariners are bullish on his stuff, which includes a high-90s heater that misses bats and 12-6 slider with some two-plane movement. He also has a changeup in his back pocket that was his best secondary pitch at the University of Florida, where he blossomed into a 2018 first-round Draft pick. And Mariners president of baseball operations Jerry Dipoto is always open to giving former first-rounders a look. Kowar was acquired in the Jarred Kelenic trade with Atlanta.

RHP Joey Krehbiel
Previous team(s): Orioles, Diamondbacks, Rays
The stuff: 4-pitch mix

Krehbiel caught on with the Mariners after being outrighted by the O¡¯s in November and electing free agency. He has 74 innings of MLB experience, most in 2022, when he carried a 3.90 ERA and 100 ERA+ in 56 outings for a Baltimore team that leaned heavily on its bullpen. Last year, his walk rate climbed to 14.2% at Triple-A, where he spent most of the season. He adds intrigue given his diverse arsenal, with a four-seamer, cutter, slider and changeup.

RHP Collin Snider
Previous team: Royals
The stuff: 28.2% hard-hit rate in ¡®23 (league average was 39.4%)

Claimed off waivers on Feb. 6, Snider has 62 games of MLB experience, over which he¡¯s carried a 5.93 ERA and 72 ERA+, with nearly as many walks (28) as strikeouts (33). But he¡¯s the prototype ¡°Steckenrider Bucket¡± pitcher given the underlying numbers, which show a potential five-pitch mix. He also kept the ball off barrels last season, with only three homers surrendered, while generating a 52.9% ground-ball rate (league average was 43.1%).

RHP Carlos Vargas
Previous team(s): Guardians, Diamondbacks
The stuff: 99.4 mph average fastball

Anyone who can touch triple digits will get a look, and Vargas¡¯ heater would¡¯ve been MLB¡¯s seventh-fastest last year if he had enough innings to qualify for leaderboards. His problem has been harnessing it, evidenced by an 11.9% walk rate over four Minors seasons and an 18.2% clip in five outings with the D-backs last year. Acquired in the Eugenio Su¨¢rez trade, Vargas should see action in the Majors this season, even if he doesn¡¯t win one of the 1-2 available bullpen spots this spring.