Why the Seattle Mariners must consider moving Luis Castillo to the bullpen
The money means nothing. Same goes for the accolades.
Personnel decisions can't be made based on a financial investment or a player's profile. All that matters is what the brass thinks that player can do.
The Mariners' acquisition of pitcher Luis Castillo and his contract extension are key reasons they broke a 21-year playoff skid in 2022 and won the AL West Division last year. La Piedra" (The Rock) was a model of consistency over that stretch - with his ERA ranging between 3.17 and 3.64 during his first four years in Seattle.
But this season, the three-time All-Star hasn't simply been underperforming - he's been one of the worst starters in MLB, with his ERA sitting at 6.57. His most recent start came in a loss vs. the White Sox, in which the 33-year-old gave up four earned runs in four innings while surrendering two homers.
The sample size isn't mountainous, but eight starts in, it's hardly a molehill, either. And with Bryce Miller - who's been sidelined because of an oblique injury - set to return, the M's may have to make an important decision soon: keep Castillo as part of a six-man rotation or move him to the bullpen. And if he keeps pitching the way he has, the latter seems like the best option.
Yes, Mariners president of baseball operations Jerry Dipoto said before Castillo's last start that the bullpen or Triple-A wasn't a consideration right now. The reason? "If you go to the bullpen, you don't maintain your pitch volume for very long. And that's the worst thing that could happen to the depth of our starting rotation is taking one of our top six starting pitchers, send them to the bullpen, and then 10 days later, their pitch volume is no longer a factor."
But what if one of your top six starters isn't pitching like someone who belongs in the rotation? This isn't like last season, when Castillo had a 4.44 ERA through his first five starts and a 3.95 through his first eight. No, he wasn't playing at an All-Star level, but by the time June came around, he was back down to 3.03. What we're seeing now from the Dominican is an entirely different kind of stretch. He's been hurting the team. How much longer do you give him?
It's not as if the Mariners (20-22 after Monday night's win at Houston) have much of cushion to experiment. This is a club many thought would be playing in the World Series, yet entering Monday they find themselves two games back in the worst division in Major League Baseball.
Also, the rise of Emerson Hancock - who's playing near an All-Star level with his 3.21 ERA and 1.01 WHIP - may force Seattle manager Dan Wilson to choose between Miller and Castillo. Right now the plan is to have a six-man rotation, but if Miller is decent and Castillo continues to struggle, is moving Castillo to relief such a bad idea?
It's also not easy to relegate a player with a track record as proven as Castillo's. I'm sure just about anybody in Wilson's position would be wondering "is the next start the breakthrough?"
Still, Castillo in his current form - despite the $24 million he's making - is not a sustainable component of the rotation. But that doesn't mean he couldn't reinvent himself as a late-inning mainstay.
ESPN's Jeff Passan brought up the idea of Luis going to the 'pen while on Seattle Sports radio last week. And as Paul Taylor of Sodo Mojo pointed out, Castillo has been extremely effective in the first inning this season (.401 OPS allowed), compared with an overall OPS allowed of .849.
Coincidence? Perhaps. Although Castillo's velocity has been at its best in the opening inning this year. And he could also serve as the glue for a bullpen that's been overrun with injuries lately.
Of course, egos tend to be Cybertruck-sized in MLB. It's one thing to want Castillo to slide into the bullpen - it's another for him to do so willingly. Hall of Famers such as Dennis Eckersley and John Smoltz made the adjustment and dominated in their roles. But it's hard to say, "I'm not what I was" before you can think, "Here's what I could be.
Perhaps in a couple of months, if Castillo is dominant again, we just look back on this as the worst month-and-a-half stretch of his career. But drop-offs happen in a hurry in this league. Just look at Félix Hernández, who had a 5.55 ERA in 28 starts at 32 years old. Yes, he had a lot more mileage on his arm than Luis does, but his final years weren't marked by ups and downs so much as they were a steep decline.
There have certainly been some pleasant surprises with the M's this year. Second baseman Cole Young playing like an All-Star is chief among them. There have been some not-so-pleasant ones, too, though - namely in the form of Cal Raleigh's bat and Castillo's arm.
Nobody is going to replace Cal full-time behind the plate anytime soon. Luis, on the other hand, could see a role change.
If taking him out of the rotation is the right move, Wilson has to do it. Castillo's past contributions won't be forgotten - but if the situation calls for it, they may need to be discarded.
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