The Seattle Mariners 2024 Season Outlook

Tristan Casady
9 min readApr 15, 2024


How the Mariners stack up heading into a pivotal season for the franchise

The Mariners 2024 season is underway after a Spring Training that saw some key injuries, questionable pitching, and explosive offensive production (in the Arizona climate, that is). This came on the heels of a roller coaster of an offseason for MLB in general after the Dodgers’ spending spree and some big name free agents remaining unsigned until the start of the regular season. The Mariners had a rather tumultuous offseason of their own in which various narratives surrounded the team’s dedication to winning in 2024. Ownership refused to increase payroll despite reports that they would allow the front office to do so, leading Jerry Dipoto and co. to salary dump some key players from the 2022 playoff run and ship off the former face of the rebuild. Instead of using it as an excuse to stand pat, the front office once again got creative in augmenting the roster for this season. There were a ton of change this offseason but the overall core and farm system remains mostly intact, now the question is how that translates to on-field success in 2024. While there is certainly room for skepticism around the players they brought in, I do believe that the roster is in a better place than it was on the final day of the 2023 season despite the anemic start to the 2024 season.

Make no mistake, if this team is successful in 2024 it will be on the backs of its pitching staff, specifically its starting rotation. The front office decided against trading away the two breakout rookies from last season in Bryce Miller and Bryan Woo, instead opting to keep what should be (once again) one of the best rotations in baseball together. I do want to highlight some important caveats here. There are some very real depth concerns after subtracting Marco Gonzales and Robbie Ray while also passing on free agent starters (the Blake Snell homecoming was never going to happen). Though it does not seem to be serious, the depth is already being tested as Emerson Hancock — who is not the special arm the Mariners envisioned when they took him 5th overall — is slated to join the rotation while Woo deals with elbow inflammation. This rotation was remarkably healthy in 2023 if you exclude Ray and Gonzales, and it would be foolish to expect the same luck in 2024 — just take a look around the league! Beyond Hancock, reinforcements are few and far between should another starter go down. Despite these concerns I think this rotation is still the best in baseball. I see two legitimate Cy Young candidates from Kirby and Castillo despite their early struggles. You could make a case for a third in Gilbert based on his early returns and I fully expect Miller to have a solid season with that shiny new splitter. Once Woo returns, I think fans will be pleasantly surprised by how quickly he asserts himself as one of the best young pitchers in the league. Expect a lot of Pitching Ninja clips from Mariners starters this season.

Perhaps the biggest question mark surrounding this roster is the bullpen. The three-headed monster is down to one after Matt Brash and Gregory Santos went down this Spring. Less important — but still valuable — arms like Jackson Kowar and Eduard Bazardo are set to miss significant time. The team traded one of their best high leverage arms from 2023 in Justin Topa and a very solid rookie in Isaiah Cambpell. Andrés Muñoz, Gabe Spier, Trent Thornton and Taylor Saucedo all look healthy but there are some serious holes to fill to start the year. The team filled one already by signing flamethrower Ryne Stanek who has looked phenomenal to start the year. The rest will be an assortment of the waiver claims and one-year deal guys who the Mariners love to target for their pitching lab. Is it an uninspiring bunch? No doubt. But I would keep an eye out for a guy like Tyson Miller, a late-twenties journeyman who could be on the Paul Sewald track after working with Mariners pitching development this spring to great success. The rest will just need to hold it down until Brash and Santos return. While I don’t feel great about it, I do think this team has earned the benefit of the doubt when it comes to constructing a competitive bullpen. If this unit can tread water until Summer, the pieces are in place for the kind of dominant bullpen that can carry you deep into the postseason.

Is this the year the offense carries its weight? Given the budget they had to work with, you cannot fault the front office for their effort in trying to improve a very mediocre offense. After the 54% controversy and uninspiring addition of Luis Urías, the Mariners brought in Mitch Garver to serve as the first full-time DH since Nelson Cruz in 2018. This is a fundamental shift from how the front office viewed the DH role in previous seasons when it was used as a cycle-through position to get guys off their feet. Does adding Garver limit some of the lineup versatility enjoyed in years past? Yes. Does that ultimately matter if Garver hits at an elite level day in and day out? No. If he can stay healthy, this could end up being one of the best under-the-radar moves in all of baseball. We’re talking 35-homerun potential here, something the Mariners have not had since Nelson Cruz. The other major addition — this time via trade — was bringing in Jorge Polanco to solidify second base after years of misfires at that position. Polanco is a far better player than Kolten Wong and Adam Frazier ever were, so I feel pretty strongly that he will break the post-Robinson Canó curse and produce in the middle of this lineup. The key here — as is often the case— is health.

Jorge Polanco in the opening series of 2024

The team also made a number of other moves in an attempt to fortify the roster. To the joy of many Mariner faithful, the team re-acquired Mitch Haniger in a rare veteran-for-veteran trade with San Francisco (or more cynically, a trade of bad salaries). Mitch had a disaster 2023 season and has not played a full season since 2021. Of all question marks on this roster, this could be the most impactful. If Mitch returns to his 2018 or 2021 form while playing at least 80% of games this season, it would do wonders for this lineup. However, I’m much more inclined to believe he’ll provide closer to league average production with the other Mitch (Garver) clogging the DH role, forcing Haniger to play a sub-par right field— even if he stays healthy. The Mariners also acquired Luke Raley this Winter to add more thump to the lineup and serve as a contingency plan at first base if Ty France struggles yet again. While he had a very solid 2023, I do think it will end up being more of an outlier than a baseline. The Rays go to great length to protect their hitters from unfavorable matchups and moving to a pitcher-friendly environment like Seattle could lead to a dip in production. Additionally, much like the other offseason additions, he sports a rather high strikeout rate. Didn’t the front office say the reason they cut ties with Eugenio, Teo, and Kelenic was to fix the strikeout problem? I guess we’ll see about this one. I’m sure I’m not alone in this thought but the Mariner’s handling of the third base position is particularly frustrating. Let me start by saying that offloading Geno was not a bad move in a vacuum, as I do not love what he brings to the table offensively. But when the front office decides to replace that offense with a platoon of (hopefully) replacement level hitters in Luis Urías and Josh Rojas who have serious defensive concerns, I don’t get it. While I still think Rojas and Urías could be valuable players, I would not be surprised to see the platoon tandem axed in favor of an every day third baseman come Summer.

As for the returners from last year’s roster, there is much less to speculate on. The franchise cornerstones of Julio, J.P., and Cal should all build upon their 2023 campaigns. Slow start aside, there’s no reason to think Julio can’t vault himself into MVP contention after the work he put in this offseason. I think J.P. will only get better and Cal should at least maintain what he did last season as one of the best catchers in the American League. That leaves the incumbent first baseman and one of the plethora of corner outfielders the Mariners ran out last season. For those who know me, they know I’ve never been high on what Ty France brings to this team. I do think there is value in a bat that won’t strikeout at a high clip in a lineup that does just that, yet I just don’t see Ty making a drastic improvement to his approach at the plate or an uptick in power, which are both things you need from your first baseman. If the rest of the lineup preforms to the level they’re capable of, then it will be much more palatable having Ty hit near the bottom of the order. Finally, the Mariners chose to role with Dom Canzone as the final outfielder after a strong Spring. Based on what Jerry has said publicly, we can assume the team is very high on Canzone and thus will likely give him plenty of run to start the year. There’s no denying the power potential in his bat but you cannot reasonably expect him to immediately be an above league average contributor (just look at Taylor Trammell) and oh man does he swing and miss. At least Dylan Moore is still a Mariner and we can rest easy knowing he’ll crush left-handed pitching and play formidable defense.

Dominic Canzone in 2024

There is room for optimism here despite the concerns. Health is a difficult thing to predict and break-throughs are always in the cards for young hitters. The most important thing this lineup can do is stick to the approach. We know how difficult it is to hit in Seattle during the Spring but if one through nine in the order are working quality at bats, laying off the spin (and boy do they need to do this), and making contact with pitches in the zone, this offense will find success over the course of an entire season. There’s too much talent here for that not to be the case if they all stick to the plan. The Mariners made a commitment to having a better offensive strategy by bringing in Brant Brown to serve as an offensive coordinator; now it’s up the players. There will be growing pains but I expect improvements from last season when opposing teams found great success throwing countless breaking pitches against Mariners hitters. We already know the pitching will be very good, the lineup’s ability to execute their game plan is what will carry this team to a deep playoff run.

Fortunately for the front office, the farm system is in a great place offensively due to the trio of first round picks in last year’s draft — Colt Emerson, Johnny Farmelo, and Tai Peete — and the continued positive development of other top prospects. Keep an eye on Lazaro Montes as a guy who could quickly become one of the best power hitting prospects in baseball. More advanced prospects Cole Young and Jonatan Clase could reasonably find their way to the big league club by the end of Summer, especially if guys like Luis Urías and Dominic Canzone struggle or hit the IL. Meanwhile, the Mariners may find themselves in a situation where a consensus top-100 prospect like Harry Ford could be made available due to Cal Raleigh’s stronghold on the catching position for years to come. The Mariners have never been shy on adding players via trade during the season and I can’t imagine this year will be any different. After opting to not add an impact bat during free agency, could the front office bring one in via trade? I wouldn’t rule it out. Regardless — and I know fans don’t want to hear this — the Mariners are set up for success in 2025 and beyond, even if they fall short in 2024.

Jonatan Clase in the 2023 Futures Game

Despite a slow start to the season, this is the deepest team the Mariners have had on paper in many, many years. They will require patience — and I cannot stress that enough — but when things click this should be a very fun group to watch. With the AL West seemingly wide open and a lackluster AL Central division, now is the time to strike.

As always, Go Mariners.

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Twitter: @tristancasady