The Mariners Pitching Dilemma 6/03/2026

LAB REPORTS

What I think is going to happen with Bryce Miller, Luis Castillo and eventually, Kade Anderson

Let's get this out of the way in the beginning. I am not sourced on this matter and if you would like official plans from the team, follow the teams beat writers, like Adam Jude. He broke it down a few days ago Here.

Let's rewind to 2024. Bryce Miller was a monster, with a 2.94 ERA and 0.97 WHIP. Last year, he battled though bone spurs in his pitching elbow and never got on track. His ratios aren't even worth mentioning, considering how out of whack the season was. Suffice it to say, he was not himself.

2026 was supposed to be the year Miller got back on track, and the Mariners would have a dominant 5-man rotation of Bryan Woo, Logan Gilbert, George Kirby, Luis Castillo, and Miller. They had some promising prospects on the farm (more on that later) but this was set to be their five.

Unfortunately more bad injury luck caused Miller to start this year on the IL for an oblique issue. Enter: Emerson Hancock. What was supposed to be a stopgap option for a couple weeks has turned into one of the Mariners most reliable players. He certainly would not be booted from the rotation when Miller was deemed healthy enough to return. So who would be?

Luis Castillo has been a rock for the team for years and is well respected in the locker room. He has been on the decline though and this year the numbers started to get ugly. Clearly the worst of the 5 pitches, he would seem to be the logical choice for Miller to replace. It's not always that simple, of course.

The Mariners likely did not feel comfortable enough to ask Castillo to take a reduced role to the bullpen. So they approached both he and Miller about a "piggyback" idea where the two pitchers would split a game's 9 innings between them. It was an awkward, clunky idea that would surely only be a temporary placeholder until more clarity could be had or a rotation spot opened up through further injury. Except Seattle has been one of the only healthy rotations this season, with none of their starting pitchers missing time, outside of Bryce's original late start.

I believe that they have been slow playing the demotion of Castillo, out of respect to him. Something to this effect: "at first we will piggyback, switch back and forth who starts, then we'll space them out with a 6-man or skipping starts of other pitchers." Using offdays and creative ways to delay the decision, hoping they did not have to officially tell Castillo he was no longer a starting pitcher.

But Castillo is fighting hard for his job. Since mid-May, he has a 3.18 ERA and 1.06 WHIP. Miller over the same timeframe has a 1.71 ERA and 0.85 WHIP as one of the best pitchers in baseball over the small sample size since his season debut. Miller looks to be a Top-30 pitcher again. The piggyback has been a rousing success. But they have to change it. It's frustrating both pitchers, and the tension has been obvious in the dugout and in interviews. Miller also deserves a shot to be fully stretched out and be able to properly raise his pitch count. And on days where he is dealing, he should not have to come out of the game just because it's "Castillo's inning."

Currently, the plan is to switch to a 6-man rotation for a couple turns through the order. It looks as though Hancock may have a skipped start planned for next week. This can only carry on for so long. Hancock for what it's forth, has had a plummeting iVB for weeks, and it's reached a concerning level. The results have still been stellar, so there's no worry of him being the one losing his spot currently. But if poor results catch up with the reduced stuff, and create a string of bad results, he could very well be the one that gets removed. The huge caveat there is that Castillo would need to continue pitching well, and I'm not sure that's particularly likely.

So what about those kids on the farm? Some of you may be surprised I managed to avoid bringing up Kade Anderson's name to this point. He's been hands down the best pitcher in the upper minors this season, and let's not forget that this is his professional debut. His rapid ascension to the majors would otherwise be nearing it's end, in the form of a major league promotion. The only issue for Anderson is the team he plays for. A rare healthy starting rotation that was deep to start and then has added an emerging Hancock to the fold. Anderson now has to leap more than 1 guy, which is unfortunate, considering how exciting he is as a pitcher.

One thing I will speculate on. If they are willing to mix-and-match things like piggybacking, 6-man, skipped starts. And spreading that throughout the 5-6 starters they have, then Kade might be only one injury away from a promotion. Or in the scenario where Castillo gets the true permanent boot to the bullpen, Kade could be promoted at any moment, in a 6-man type of setup. Once this current shuffle finds its landing spot, Kade might well be "next-man-up."

That in itself, is a reason to stash Anderson, as those who follow me on X have heard me banging that drum. He's worth rostering in mid-sized leagues with an N/A or where many prospects are already owned. And certainly in deeper formats. I've personally made sure to roster him even in shallow leagues, as I believe his impact will be large. These are not all good player comps for his skillset, but the quartet of Chase Burns, Jacob Misiorowski, Cam Schlittler, and Nolan McLean all emerged last year off the wire and have risen to being aces in less than a year. Having a lower strikeout ability than some of those guys is hardly an insult to Kade, but he possesses their type of talent level and ability to emerge as one of the biggest waiver wire adds of the year. Up to you if you want to leave that out in the open for your leaguemates...

They will find a way to bring him up this year, I'm entirely convinced. He's just making a mockery out of Double-A. And the Mariners as an organization have a long history of promoting their top pitching prospects straight from Double-A to the majors. So a stop in Triple-A may not even be in the cards for Anderson, as the hitter friendly PCL is a place they like to avoid sending their best talent.

Anderson could be an injury away, a permanent demotion away, or simply just another month-and-change away. It is entirely possible the Mariners just do not care about any of the above factors and just choose to promote him anyway. He is already forcing the issue with his stellar pitching, and they will want him as part of the big club. In that scenario, he could just force their hand to do something more drastic with Hancock, a trade, or just bring Kade up to be thrown into the piggyback dance all over again. It is obvious to anyone who has watched him that he will be one of their best pitchers the moment he arrives. And that day is drawing nearer.

And after all of that, we still have not mentioned the arguably most-talented prospect they have in Ryan Sloan. Armed with elite stuff and an arsenal most prospects dream of, he too has been demolishing Double-A. Like Anderson, if he played for a different organization, he may be getting called up before Father's Day. As is stands, he is likely in line after Kade Anderson. Who is after Castillo, who is after Hancock, who is after Miller, etc.

One thing is clear, the Mariners have an embarassment of pitching depth. It is a great problem to have, especially in today's age of pitching injuries. The Mariners have been healthy to this point, and thus not needed to tap into their depth of their farm system. But that day too, is coming. And when the best-5 of these 8 guys all find their eventual landing spots, it's going to be one of the best staffs in all of baseball.

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