26-Man Roster Analysis
We're through the first full month of the 2024 season, so let's dive into the Mariners' roster.
When the 2024 season began, my evaluation of the Seattle Mariners was tentative: More upside than any roster under Jerry Dipoto, but more risk than the previous two teams. The results have shown more of the latter than the former.
ROTATION
Luis Castillo, RH
Castillo struggled in his first three outings, allowing four earned runs and 25 total hits in 15.2 innings despite a shiny 18-2 K/BB ratio. It was simply too much plate, particularly with runners on base, and even more specifically with left-handed batters.
Since, however, Castillo has been more consistent with his fastball location, has executed the slider with two strikes, and his changeup has given him some play versus left-handed batters and, voila!, he’s back.
Overall, the Mariners’ Opening Day starter is throwing more four-seamers and sliders at the cost of his changeup and two-seamer, but his usage has bounced around, depending on the outing. But the slider whiff rate is up 6% over 2023 and I think that may be Castillo’s most important pitch, at least when it comes to taking a half step forward from a year ago in terms of consistency.
The two-seamer has been wrecked this season, though it’s a small sample and I expect it to improve moving forward.
Everything Castillo throws is firm, so movement and location are crucial to his success, but he’s a control-over-command power arm, so expecting a bumpless ride through September isn’t a wise gamble.
George Kirby, RH
Kirby’s fastballs, plural, have been insanely effective, and combined he uses them 63% of the time. Opponents are batting .143 off the two-seamer and just .227 with two extra-base knocks versus his four-seam heater, including a 28.4% whiff rate. The four-seam success is not new, though he may be taking it to a new level this season with more extension.
Where Kirby has improved most in 2024 is the swing-and-miss on his curveball, up to 37.5% for the year. He throws it just 8% of the time and it’s not a pitch he goes to finish off hitters much, but it’s helping him create vertical pitch value, one of the reasons his four-seamer is so deadly.
Kirby’s hard-hit rate of just 30% leads all Mariners starters and is No. 7 in baseball. He’s missing the barrel and what may seem like an unsustainable rate of 6.3%, but he logged a 7.5% mark a year ago, also tops on the club.
Ignore the 3.76 ERA attached to his name, because his 2.08 FIP, 3.10 xFP and 2.84 xERA tell the real story, but the one truly unsustainable number here may be the 4.3% HR/FB rate he’s sporting. A year ago, Sonny Gray led baseball at 5.2%, and no qualified pitcher has posted a rate under 5% since Garrett Richards in 2014. But I wouldn’t expect that performance to stray too far.
Logan Gilbert, RH
Gilbert has been terrific in his first seven starts, with an increase in walks the only blemish on an otherwise large step forward in overall performance.
But Gilbert is also missing more bats — 28.2%, up from 24.5% in 2023 — thanks to fewer four-seamers, replaced by more curveballs and a new 92 mph cutter.
Gilbert’s slider, which he’s actually throwing a bit less than a year ago, is generating whiffs on 40% of swings, and he’s commanding the pitch better than ever. His splitter (15% usage) is destroying lefties and righties alike with a 53% whiff rate.
The righty has no splits right now, either, but the key to his success versus lefties has been the cutter — not the splitter, which he’s using more versus RHBs than LHBs.
Once Gilbert gets two strikes on a batter, it’s lights out in 2024. After two strikes, opponents are batting .110/.198/.195, but overall execution in hitter’s counts may be the biggest key to his improvements thus far. When down in the count, batters have managed a .216 average and .297 slug.
Gilbert is one of four legitimate Cy Young candidates on the club.
Bryce Miller, RH
Miller has been one heckuva surprise. Despite a so-so outing Sunday versus the Astros, Miller’s progress has been enormous, and it’s largely due to his improvement versus left-handed batters. Despite the two homers he allowed in his latest outing to lefties, LHBs own a .128 average and .209 OBP off the righty, and the .346 slug includes five homers.
And the success isn’t just based on the splitter. Not directly, anyway. Miller’s four-seamer has eaten lefties alive (.111/.215/.250), including a 28% whiff rate. There’s still work to do with everything, particularly the slider, but it’s a full enough arsenal with weapons to cover the entire zone. It’s a gear he didn’t have in 2023.
If Miller’s performance holds up, the Mariners have the best 1-4 in baseball.
Emerson Hancock, RH
Hancock has had three good starts, one good-enough start, and two poor ones, but tis the norm for a No. 5 starter.
Prior to the season, the righty had done nothing to suggest he could be that. Not to me anyway. But he’s missing a few more bats than a year ago thanks to more fastballs and changeups, and the occasional flash of a better slider. He’s throwing strikes, generally, but his stuff is ordinary so his command has to be very good or he’s susceptible to a lot of hard-hit balls.
The pitch that seems to come and go for him is the two-seamer. At times, it’s a great early-count pitch, forcing right-handed batters to honor the inner edge and occasionally getting lefties to lean out over the plate, making them more vulnerable to backfoot sliders.
Hancock may be losing his rotation gig soon with Bryan Woo up to 66 pitches in rehab, but this is a solid development for the Mariners. It’s real growth and a viable No. 6 starter in case of injury.
Hancock has more room to grow, I think, too, most notably in fastball command.
BULLPEN
Andrés Muñoz, RH
Muñoz has been very good aside from a few outings when he lost his control (April 5 vs MIL), or command ( April 21 vs COL). He hasn’t allowed an earned run since that Brewers game, a tally of 10 appearances and 10.2 innings, including three separate four-out efforts, and one five-out performance versus the Atlanta Braves.
Results of Munoz’s three pitches are all elite; His four-seamer (21.6%, 98.6 mph) is generating 19% whiff (down from 30.5% a year ago), but opponents are 1-for-8 when they put it in play, a measly single. His slider (46.5%, 88.4 mph) is getting 41% whiff and a .200 BAA with just one extra-base hit. The two-seamer has been huge for the Mariners ace reliever: .154 BAA, no extra-base hits, 46% whiff on 32% usage.
Aside from his four-walk implosion, Munoz has issued just three bases on balls in 13 innings, with 50 batters faced. Clone him.
Gabe Speier, LH
Speier, also aside from a three-walk outing, has been terrific, and his success is not without balance. While lefties have stood no chance thus far (.111/.238/.278), right-handers are batting just .211/.292/.211 with no extra-base hits.
And the southpaw is doing it in a quite unique manner. It’s not new, but he’s leaned further into throwing more fastballs to lefties and fewer of them to right-handed batters. His slider usage versus righties is up 8% from 2023, and it’s down 9% to lefties.
Speier had issued with just two bases on balls prior to Friday’s outlier, and unless and until Gregory Santos returns or the club acquires another reliever, the southpaw should be used in as many high-leverage spots as the club needs.
Ryne Stanek, RH
Stanek should be better than he is. His stuff is probably Top 10 in the league, led by a fastball consistently 97-99 mph. But his four-seamer gets hit because he 1) struggles to land his slider or splitter and 2) he doesn’t command it well.
Stanek lacks extension, so his velocity is a plain 98. And while he hasn’t allowed a single hit versus either secondary thus far (0-for-13 when put in play), he hasn’t been consistent enough in throwing competitive versions.
When he does, they are both devastating. The slider has induced a 50% whiff rate an the splitter over 31% through the Astros’ series. Getting ahead is crucial for Stanek, but hitters tend to ambush the fastball early in counts, and when he’s behind he gets torched (.300/.563/.600).
Stanek’s issues finishing off hitters are simply a byproduct of the above. I wonder if he starts throwing more sliders early, including a get-me-over type down and away.
Tayler Saucedo, LH
Saucedo has been very good, missing more bats than ever and still generating 55% ground balls with his sinker and changeup. He’s throwing even more two-strike changeups to RHBs and so far has ditched the slower breaking ball.
Sauce hides the ball well, so his four-seamer will sneak up on hitters a bit, especially when he’s shown he can throw the slider for strikes. He’s not a late-innings, high-leverage type, but he’s certainly gotten the club out of some tight jams with weak contact and added swing-and-miss this season.
Austin Voth, RH
Voth is the prototypical middle-long reliever, and he’s done his job and then some in 2024.
He was knocked around in Milwaukee for three earned runs, but other than that has yielded just one earned run on eight hits over 13.1 innings. He’s not walking batters (4.7%) and he’s running the highest strikeout rate (24.5%) in his career other than a 9-game run in the Nationals’ rotation back in 2019.
Left-handed batters are just 3-for-26 off Voth, thanks to a cutter-fastball combo and a pretty good curveball away. He’s left the cutter up and over the plate to righties, however, and his slider has bee hit hard thus far. In its rawest form, Voth slider has potential, but too much plate is always a bad idea.
Tyson Miller, RH
Miller creates angles and spins a slider reminiscent of Paul Sewald, and neither his breaker or fastball gets hit much. While he’s not overpowering at 90-93 mph, he gets good extension and the deception helps his heater play up.
Miller started the season in Triple-A Tacoma and is a candidate to be replaced by Santos or a trade acquisition, but he’s done the job of a middle arm (34% K, 3% BB, 2.08 ERA, 87% LOB).
Cody Bolton, RH
Bolton owns a four-pitch mix, unique among relievers in 2024, led by a 93-96 mph sinker, power cutter, a traditional slider, and a changeup, and he uses them all regularly, with none being thrown more than at 35% or fewer than 13% rates.
Bolton’s cutter is key to his entire operation, keeping hitters off the sinker, and setting up a slider with a chance to miss bats (but hasn’t yet). His changeup appears to be a show-me pitch at this point, but it’s firm and he remains confident enough in it to keep throwing it some, primarily versus left-handed batters (23%).
Trent Thornton, RH
Thornton can spin it, posing 2900 rpm on his low-80s slurve, and 2800 on his slider. He’s also 94-95 mph with two fastballs. Still, Thornton hasn’t found a way to generate the strikeout rates of a quality big-league reliever (20.4%).
He does throw strikes but will allow the ball to be lifted and with high contact rates, even when a batter chases, Thornton doesn’t belong in close-and-late scenarios. But he’s been plenty good in the role the club envisioned, including dominating right-handed batters so far (3-for-24, 0 XBH).
OUTFIELDERS
Julio Rodriguez
The Mariners’ lineup will go as far as Rodriguez can carry them, and that’s not to say he doesn’t have help. But he’s the lone alpha, and right now it’s very beta-like power production.
The 23-year-old continues to answer the bell and play very good defense, and his batting average is acceptable. He seemed to have found a better path to contact on the Colorado-Texas road trip but has since gone back to a very inconsistent launch angle.
His swing decisions, however, are the key to everything.
Rodriguez has six barrels all season and just three since April 12. He had 57 a year ago, including eight in his first 27 games. His chase rates aren’t an enormous issue at the core, but he must force pitchers to throw him better pitches to hit by laying off hard stuff in off the plate.
His contact rate on fastballs in off the plate sinks massively, depending on the exact locations, and his slug goes with it because it’s very difficult to get the barrel there without jumping out front early.
It’s simply not a pitch location on which Rodriguez should be aggressive. His career chart shows he’s best out over the plate.
One would understand protecting the inner half with two strikes, but …
Yeah, it’s also on the first pitch of his PAs, and it can be maddening to watch.
Julio has always generated a bat wrap as way to get started, and generate momentum, and he has tremendous bat speed. But it also makes it tougher to get to 94 mph in off the plate, and a lot of these pitches are offerings NO ONE is getting the barrel to with any regularity whatsoever.
This approach simply needs to go away or clubs are going to live outside the zone and allow Rodriguez to continue to get himself out and settle for a lot of singles.
Mitch Haniger
Haniger entered the Twins series 15 for his last 82 with a 34.1% strikeout rate. He’s playing too much, although it was understandable early — he was hitting, no one else was — and criticizing Haniger or his abilities isn’t fair as a result.
Haniger hasn’t anything but fastballs in 2024. He’s .271 with a .492 slug versus heaters, but 8-for-54 when an AB ends on anything else, including a 29% whiff rate.
I mentioned on Baseball Things, and elsewhere recently, an idea Seattle may consider down the line at some point to open up more time at DH for Haniger and others, and perhaps make it easier for the club to acquire offense this summer: Make Mitch Garver the backup catcher and rotational DH until September when Blake Hunt can be called up as part of roster expansion.
But until then, Haniger probably shouldn’t play more than 3-4 times a week, but that means someone else has to perform well enough to warrant the time. Maybe we’re seeing signs of some of that from…
Luke Raley
Raley started the season 3-for-12, then went five for his next 32 with one extra-base hit. He did just hit his first homer of the year and is six for his last 15 with four strikeouts and two walks. Maybe it’s a sign.
Raley wasn’t necessarily expected to perform versus left-handed pitching, but when he stays short he can hang, and it probably should have been a Haniger-Raley-Canzone timeshare for two outfield spots, but performance and injury gave that no chance to develop.
Raley has chased too much for consistent contact, but there are signs he can be helpful still this season.
Dominic Canzone
Canzone was the best hitter on the roster when he got hurt, and had started to corral the strike zone. He should be back in late May — he started running and throwing 10 days ago — and add some more pop to the roster.
Canzone is a 40-grade defender, but isn’t any worse than Haniger at this stage and could work his way to 45 status, but it’s playable if he hits.
Jonatan Clase, Sam Haggerty, Samad Taylor… Cade Marlowe
The trio has amassed a total of 42 plate appearances — 28 by Clase — with eight hits and just one for extra bases. The Canzone injury and Raley’s struggles have set the Mariners to the minors earlier than they would prefer.
Many seem to prefer Marlowe in a bench role right now, but considering the lefty bat’s issues with swing-and-miss in Triple-A I would pass, too.
Marlowe enters Tacoma’s next series with a 37.3% strikeout rate in the PCL, including multiple strikeouts in 19 games, four starts with at least three punchies, and he’s not hitting for enough power to justify it to any extent — eight extra-base hits all season.
Marlowe had some success in Seattle last season, but expecting this version of him to put up quality at-bats in the big leagues is a not-so-funny joke. Haggerty is a better option right now, considering this is an off-the-bench role, and if they end up wanting to swap Leo Rivas for another hitter, Nick Solak, Jason Vosler, and Brian Anderson are probably better options than Marlowe at this point.
For the record, the club’s 40-man is easy to manipulate right now. Matt Brash can be placed on the 60-day IL, and the Mariners could simply decide between Taylor, Haggerty, and Marlowe on that front, too. Sammy Peralta’s spot on the 40-man may be the weakest. He’s a junkball lefty (86-90 mph, SL, CB, CH) with 40 control and no chance to miss bats.
CATCHERS
Cal Raleigh
The 27-year-old Raleigh has had an interesting 2024 so far. His strikeout are up 6%, his walks are up a bit, too, and he’s batting just .210. But he’s getting more time from his weaker right side, where he’s batting just .200. But he has four homers as a righty this season, and it’s carried his wRC+ to 111, matching his 2023 mark.
I still think Raleigh can hit .240 or better, but his power makes a significant impact and because he draws walks and plays good defense, Seattle can live with the low average and OBP numbers a bit.
Raleigh has had huge trouble early versus changeups and splitter — 0-for-23 when he makes contact, plus a 58.6% whiff rate — but he’s been better versus fastballs and breaking balls than in previous seasons.
The league, however, is going to throw him more changeups and splitters, so an adjustment has to be made there.
Raleigh is among the top 5-8 catchers in baseball to those who don’t live in 1983 (staring at batting average).
Seby Zavala
Zavala is being asked to do the impossible: Perform while getting four at-bats per week. He is 5 for his last 12 with two doubles after an 0-for-12 start, but he’s gone three, three, five, two, three, two, and now at least five days between at-bats. Tough gig.
He’s a solid-average defender who swings hard and often, but his career results suggest no split advantage — he’s actually been better versus right-handed pitching more years than not — so he’s not exactly being set up for success. The club’s offensive struggles make it difficult to get Zavala into games more often, and that may not change anytime soon, hence my Garver idea.
INFIELDERS
J.P. Crawford, SS
It really seemed like Crawford was getting it together when he got hurt — hits in five straight, contact rate up, hard-hit rate up, and he was using the whole field.
It also looked like his defense was more sound. One thing I noticed from Crawford from a more aggressive first step, nothing wasted, perhaps trusting his instincts and not relying on seeing and reacting. We’ll see if it shows in the long-term.
I expect a 110-115 wRC+ level of production from Crawford when he returns, and it seems he’s got a shot to be back in a few weeks. And no, he didn’t lose his top-of-the-order spot.
Jorge Polanco, 2B
Polanco has had several nice runs of production, but entered the Twins series with maybe the best one in tact. It’s a seven-game hitting streak with a double and two homers, despite all the strikeouts.
Polanco’s career strikeout mark is 18.6%, but he jumped from 15% to 18% to 21% to 26% the last four years as he unleashed a more aggressive swing. It’s up to 30.7% after the series in Houston, but the production has taken a step forward the last week, too. I don’t buy a .254 BABIP here, so that average will come up some as the season moves along.
Luis Urias, 3B
Urias isn’t making contact like his baseball card suggests he should — 32.7% strikeout rate entering the Minnesota series versus his career mark of 21.9% — but he’s making the most of his contact, including three homers and three doubles, is drawing a few walks (8.2%), and has driven in 10 runs from the bottom of the order in 42 ABs.
Urias’ BABIP is extremely low at .174, but I don’t like his heavy fly-ball approach (58% FB) in terms of average and getting on base, and his 20% HR/FB rate is not sustainable.
Josh Rojas, 3B
Rojas has been the savior, carrying a .360/.442/.587 slash into Target Field this week. He’s made a lot of contact, drawn walks (12.6%), and is playing solid defense.
But none of this is sustainable to these levels, which eventually means the pressure is on those struggling right now.
Rojas and Urias (and a bit of Moore) have combined for a 168 wRC+ at third base, No. 2 in baseball behind Philadelphia.
How about the San Francisco Giants and Matt Chapman, you ask? No. 25 with a 79 wRC+. Chapman is batting .215/.264/.356 with a 26.4% strikeout rate. He’ll make at least $18 million from the Giants, and unless he opts out they will pay him $54 million over three seasons.
Rojas and Urias will make $8.1 million combined this season and are not guaranteed a penny beyond 2024.
Ty France, 1B
France’s first five weeks are weird. The overall production has not been there. Strikeouts are up 4%. though not problematic in the grand scheme and the walks are up a bit, too. He’s chasing far less than a year ago, making more contact when he does chase, and his hard-hit rate is up to 46%, an increase over his career mark of 38%.
France’s xSLG is .463, but he owns a .355 mark, and honestly, it’s very strange until we look at his batted ball data.
Too many ground balls — 46%, and not enough fly balls (24.7%) to match the improved EV and HH rates. He’s also not pulling the ball much at all — 24.7%, 15% below his career mark.
Seattle’s patience with France may very well pay off, but this has to be a believe-it-when-we-see-it kind of scenario after France was merely league average in 2023 and is at it again in 2024.
Dylan Moore, UT
Moore has so many projectable skills that I’d bet big if you attached an average swing to it he’d be an all-star every season. Bat speed, foot speed that allows for stolen bases, strike zone judgment, contact ability, defensive range out to shortstop, versatility to the outfield, arm for third… he has every tool necessary, but his swing makes me wish for temporary blindness.
Still, he’s a valuable major leaguer — and the first ‘Moore’ that pops up for me in FanGraphs searches, so that’s helpful, too. Moore is nit going to hit for average, but gets on base (11.9% walk rate) and has some pop, though it hasn’t shown as much in 2024 yet. He will swing and miss though, and that’s mainly what keeps him on the bench over the long haul.
DH
Mitch Garver
Garver has struggled to string together productive games, yet to have reached base by hit or walk twice or more in back-to-back games. He’s waking and doesn’t expand the zone a lot in general, but he’s chasing the breakers at a high rate with two strikes.
Garver is 2-for-42, both singles, in ABs that end on a breaking ball, and that comes with a 47% whiff rate. He’s 13-for-54 (.241) with nine XBH (.533 SLG) on everything else and now appears to be sitting on the breaking stuff.
Garver hit .299 with a .590 slug on fastballs last season. He’s at .214 with a .500 slug in 2024. But he handled breaking ball last year — .243 average,.441 slug including six homers. He has to figure out the breaking stuff.