Roki Sasaki would fix this

The cure to the Mariners’ ills is pitching a unique 23 year old on their ability to fit his needs.

Jerry Dipoto was quoted recently in the Seattle Times as stating that the Seattle Mariners have been “preparing for years” for their chance to pitch Japanese wunderkind RHP Roki Sasaki to sign. The word choice echoed precisely the language they’d used when preparing for the international amateur free agency of Shohei Ohtani. That courtship ended in heartbreak for all, with Ohtani choosing the Anaheim Angels. The Angels squandered their time with Shohei, while Seattle received no savior and instead embarked on a rebuild that has ultimately borne fruit and a single playoff appearance thus far. Seattle’s state is far less dire in 2024-25 than it was in 2017-18. Still, they are constrained. Like a dog at the end of their lead line that’s been tied off to a street lamp, unwillingness to invest in the roster has allowed Seattle to uncover their limitations.

Sasaki, however, fixes much of that, more than any other player in the market. Sasaki is, in brief, the sport’s best prospect, already a professional for almost half a decade with success in the only international league that somewhat rivals MLB in talent. The 23 year old has lived a bittersweet route to stardom, losing his father and other close family as his family home was destroyed in a 2011 earthquake and tsunami. Skyrocketing to the professional levels at age-19 with the Chiba Lotte Marines of the Pacific League, Sasaki has been utterly dominant on the mound. He’s posted a 2.02 ERA from age 19-22 in 414.2 innings, while also shining in international play. Still, there’s been room for disappointment.

Expectations were stratospheric, and though Sasaki has averaged 98-99 mph on his fastball for much of his time, he dipped to merely 96-97 this past season, and with it his strikeout numbers slipped at least a shade as well. Moreso than his heat, his durability has been of concern, topping out at 20 games pitched in 2022 and 129.1 IP, before just 15 and 18 appearances over the last couple seasons, averaging about 100 frames. That’s not an outlandishly light workload for a comparable prospect in the minor leagues stateside, but Sasaki has been in the spotlight of NPB, with a long understood desire to pitch in the United States. That goal, along with a less-than-workhorse reputation in his young career, has made for a more harsh media environment in Japan, seeing one of the nation’s brightest stars openly fixated on an early departure. With a devastating splitter and a quality slider, Sasaki is immediately able to slot in as a rotation member for any organization in MLB, with the upside of one of the sport’s best pitchers.

What the young righty wants, however, is more opaque. Sasaki’s agent Joel Wolfe spoke to this at the Winter Meetings last week, highlighting that Sasaki is not beholden to any one market or the West Coast, and that he is open to pitches from all 30 clubs. It’s a reasonable thing to say as an agent, instead of dwindling his client’s market, but the youngster can only sign for international signing bonus pool money, limiting the immediate payout possibilities.

Seattle is, as such, in the mix financially, and boasts a few reasonable advantages. Their home park is pitcher-favorable, while their strong current rotation and track record of pitching development are worthwhile bragging points. If Sasaki is indeed open to the prospect of a smaller market or environment to grow as a player, Seattle has a relatively cozy media environment compared to the intensity of many other markets, and the Mariners have shown they are willing to insulate their players from media scrutiny when desired. Sasaki can be engaged in a city with a robust Japanese community and history, or insulate himself in a suburban silo, whichever may be his wont. Few genuine contenders can offer Sasaki both a spot to compete right away and the comfort of knowing he won’t need to be counted on to cover 180 innings immediately.

Unfortunately, Sasaki can’t hit (literally, he’s 0-for-11 with nine K’s as a pro). Luring Sasaki seems dependent on the above factors (unless he’s already set on the Dodgers, as an early, heavily denied rumor suggested), but Seattle will have to defend their process thus far. Why would a player who can choose to sign with all 30 clubs for equivalent initial money pick Seattle, when the organization has shown little willingness to invest in their roster commensurate w/their competition? Does Sasaki want to indulge the fantasy of John Stanton’s ownership group by being an underpaid star for an organization who doesn’t seem interested in even reinvesting the excess money they’d be making on his back?

Sasaki would offer Seattle a chance to justify their current rumored move, trading RHP Luis Castillo for either direct lineup support or the financial relief that they’re acting as though they need to make such an improvement. If Sasaki chose Seattle, however, a Castillo move makes sense from a baseball perspective and not simply a miserly one. Seattle could either run a six-man rotation and give some cover to Sasaki, along with Bryan Woo in particular, whose workload and frame have not indicated full confidence in a jump to 180+ frames in 2025. Trading Castillo would no longer create a clear hole that Emerson Hancock or another acquisition would need to fill, or Seattle could retain him but be bolstered with a rotation that consistently goes deep into games and can afford more easily the shorter bullpen to cover some occasional abbreviated outings. If Sasaki progresses as hoped, he’d even make dealing from the more established starters more feasible in the longer term, should such an offer line up to upgrade a position player.

It’s difficult, however, to ask a player who you cannot pay more than what Austin Hedges just received to be a salvatory force for your organization, particularly after spending the last three offseasons making it clear you’re incapable of improving without a similar low-cost godsend. If Sasaki sees what he wants in Seattle, however, the organization and the roster itself will be enriched in a way that will be exhilarating and beyond complaint.