Breaking Mariners: Yusei Kikuchi Edition

Was 2020 a sign of a breakout? Or a continuation of the same issues?

As projections for the 2021 season begin to roll in, we’re kicking off a new series here on the site where we take a projection for a particular player and two staff members argue the case for each player over- and under-achieving on said projection. Since we don’t have every projection system currently available, we’ll note them where available, but our discussions are hinged around an in-house decision on what we feel the “break point” is for that player’s projection, a number arrived at by negotiation and input from the staff that comes closest to being one writer’s ceiling and another’s floor. If there’s a player you’d especially like to see covered in this series, drop it in the comments and we’ll do our best to fulfill all such requests. In case you missed the first entry in this series, on Mitch Haniger, check it out here, and the second, on Ty France, here.

Player: Yusei Kikuchi

Yusei Kikuchi is pretty easily the biggest free agent acquisition of the Jerry Dipoto era, and got a deal that reflected ownership’s aversion to big money on wasted contracts—while he has 56mm guaranteed, the deal can escalate to a whopping $109mm if the Mariners exercise their 66mm club option after 2021. Thus far, while he’s shown flashes, he’s not produced the results the Mariners hope for. Obviously we look deeper than resultsbased analysis here, but there’s a gaping chasm between his 2019 performance (and his 2020 ERA!) and his 2020 peripherals: a 5.17 ERA to go with a sparkling 3.30 FIP in 2020, thanks in large part to a wretched 59.9% strand rate. Which will Yusei in 2020? Only time will tell, but John and Tim will try to guess.

2021 ZiPS projection: 131.3 IP, 4.50 FIP, 1.5 zWAR, Steamer: 158 IP, 4.37 FIP, 2.2 WAR

LL Break Point: 1.9 WAR

Taking the over: Tim

The thing about projection systems is that they don’t account for everything. They also know they don’t, so the projections are inherently geared towards allowing for a midpoint of a wide range of outcomes. It’s why we don’t just slap a 10 WAR target on Mike Trout every year—injuries happen, BABIP happens, lots of stuff happens. Yusei Kikuchi is a strong example of a projection that has to account for so much that a lot is lost. His first year in America involved a variety of voices in his ear, a new culture, a new son, a new team, and all sorts of other variables which would overwhelm anyone. In year two, he trimmed away some of the noise and simplified, reworking his delivery with Driveline and ditching his curve in favor of a cutter. Oh, but wait: a pandemic! A topsy-turvy and abbreviated year behind him, Yusei now settles into what will be his most normal year in Seattle yet—and yet, if you haven’t noticed, it won’t be THAT normal. Just relative to the baseline.

The ding on Yusei is always consistency. And it’s a fair one! Here’s his rolling 50-PA xwOBA:

It’s pretty all over the place! That 2019 peak really stands out. It’s worth noting, though, that he only ended up back above a league-average xwOBA at the end of 2020 after an incredibly poor start against the Padres on September 18th. But being up and down isn’t a death knell for a pitcher as long as they’re more up than down. Let’s go look at the best free agent on the market this offseason:

Trevor Bauer has had stretches where he was nearly as bad as Kikuchi’s worst and spent a lot of time in between. And yet he’s fresh off a Cy Young appearance in a season where he spent a lot more time under that league average line—just like Kikuchi did. This isn’t to say Kikuchi is Bauer—he isn’t. It’s just that it’s tempting to see him as a finished product because of the age and the long track record in another high-end professional league. He’s still changing, still improving, and there’s ample reason to think his best days are ahead of him.

Far from random variance, the concrete difference in Kikuchi’s seasons in Seattle is easy to see as a product of one pitch: the cutter. Mikey noted the cutter almost immediately after the season opened last summer, and Kikuchi kept hammering it all year. The thing about the cutter, though, isn’t just how effective it is on its own—it’s how the change in arsenal made all his other pitches better.

Baseball Savant

It’s not that simple, of course—he also added velocity that made his fastball play up, as Jake Mailhot ably noted last abbreviated spring. But the effectiveness of the rest of his pitches, especially Whiff%, skyrocketed in 2020 (and he ditched the horrendous curve.) Hitters were much more off-balance and it showed across the board except in that pesky ERA—which would look a lot better with his league-average 70.8 LOB% of 2019, instead of his worst-by-a-mile 59.9% in 2020! If you’re going to bet on one of those to repeat, it’s probably not the one that was the worst in baseball by four points.

And yet in terms of peripherals, Kikuchi managed to reach 1.1 fWAR in 2020 in just 47 innings. Inconsistency is a problem for a pitcher, and it will keep Kikuchi from becoming truly elite unless he can iron it out. Mariners fans know this well, having watched the ups and downs of James Paxton between starts. Paxton is illustrative for Yusei in this exercise, not because they’re terribly similar pitchers, but because Paxton’s good was so good it could overcome his downsides (including health, a problem Yusei hasn’t had to date) and make him an effective pitcher. But a 1.9 WAR hurdle, with his track record of health and eating innings? Yusei Kikuchi will hit the over. If he can fix all the stuff John is about to identify, he’ll do a lot more than that.

Taking the under: John

My instinct is to couch any negative statement with mentions of hopes for alternatives and belief that the opposite could be true, but it seems implied by the nature of writing for this site, so we’ll go right to the nasty bits. As long as Yusei Kikuchi is as inconsistent in his command as he has been in his first two years with the Mariners, he is going to struggle to reach his potential.

Spicy take, I know. If a pitcher doesn’t have good control they won’t be as good as they could be, film at 11. But this is a charge commonly leveled at prospects, gangly and unfinished, who are working to harness their upper-90s heat into something targeted and focused. Kikuchi will turn 30 in June, and has numbers that look more Ariel Miranda than anyone would like to see for a major free agent acquisition. It’s pure supposition, but Kikuchi’s 5.39/5.17/4.87 ERA/FIP/xFIP in the first two years (208.2 IP) of his time in Seattle can’t have helped Seattle’s front office feel confident in unlocking their bank vaults this winter. But while the peripherals are encouraging in many ways from 2020, some of the same issues from 2019 held him back again, namely consistency.

Kikuchi’s 2019 was more jarring, as he showed brilliance some days and a total loss of command and velocity on others. While his fastball velocity was more consistently around 94 mph in 2020, it still ranged game to game, and so did his command. Twice Kikuchi had starts without a single free pass, and thrice he issued four or more while failing to complete five innings. His 4.10 pitches per plate appearance was 19th-highest among qualifying pitchers, and while many of his compatriots in the upper echelons of those rankings were excellent starters, their strikeout rates (Jacob deGrom, Trevor Bauer) were elite, whereas Kikuchi’s were merely a tick above league-average, and his K-BB% was still subpar. With so many pitches needed to get each through each hitter, whether they reached base or not, it’s unsurprising Kikuchi didn’t get through more than six innings in a single start last year. Even less surprisingly, he wasn’t putting himself in positions to succeed more often than not.

Just 50.5% of Kikuchi’s plate appearances started with a strike in 2020, the third-worst rate of any qualified pitcher and a completely anathema ratio for the Mariners, who laud Controlling The Zone and frequently hammer first pitch strikes as one of their key indicators for success developmentally. League-average is a distant 60.6%, and while pitchers with stuff like Kikuchi can afford to fall behind now and then, they can’t give plate appearances away as often as Yusei did in 2020. Kikuchi lead the league in 3-0 counts, reaching them in 8.8% of his plate appearances, roughly double the league average. That is basically giving away 2-3 plate appearances per outing, and it’s a big part of how Kikuchi, even with a fortuitously low HR/FB%, had another disappointing year results-wise. Yes, he was unlucky in stranded runners scoring, but he kept waving his hand over an open flame and eventually got burned.

Yusei Kikuchi can be the Mariners best pitcher. Some days, he’s looked like it. But too often he hasn’t, whether it’s all day or just a few hitters. The good news, in theory, is that a player who is showing they can excel at the big league level has it within them to do so consistently. But even stretching back to his NPB career, consistency complaints dogged Kikuchi, albeit never seeming tied to a lack of effort. 29 is youthful in the realm of psychological development, even as it is turning the corner of agedness in baseball physicality. If Kikuchi’s consistency can manifest through a combination of greater focus, comfort, and self-awareness, Tim will be happily taking this round. But there’s a weighty chrysalis Kikuchi must break free from to spread his wings and fly.