The Seattle Mariners will take the field on Sunday at T-Mobile Park against the Kansas City Royals trying to avoid a three-game sweep at the hands of the American League Central foes.

The M's have lost consecutive one-run affairs, with Saturday's coming in devastating fashion, to fall to 16-18. And the task of avoiding the sweep won't be easy on Sunday, as the M's will likely be without Cal Raleigh. Furthermore, the struggling Luis Castillo is on the mound. He owns a 6.35 ERA thus far through six starts and was just hammered for seven earned runs in five innings on Monday night against the Minnesota Twins.

A three-time All-Star in his career with the Cincinnati Reds and Mariners, Castillo has been one of the best pitchers in the American League since the Mariners acquired him in 2022, but he's slumped this season. At the age of 33, it's fair to wonder if Father Time is catching up with him, or if this is just a prolonged early season blip.

As noted by Baseball Savant, Castillo is in just the 16th percentile of expected ERA and ninth percentile of expected batting average. His whiff and K rate are slow, as he's giving up an alarming amount of hard-hit balls. 

So, can Castillo do anything to turn it around? We spoke with Nick Pollack, the founder of 'Pitcher List,' on the most recent 'Refuse to Lose' podcast.

"Well, okay, so it is like a 95-mile per hour four seam this year. I will mention: he has one of the worst extensions in baseball. He's in the first percentile at 5.4, which means that that 95 really looks like 93 to a lot of guys because it's literally two feet less than Logan Gilbert. It's kind of hilarious when you think about that.

Now, how does he beat those projections, at least match the ones that you have? (five innings pitched, three runs or less). He is adding a cutter this year, and I am very curious if that is something that will be utilized more often for Luis Castillo moving forward. Because that's what you need. You need more pitches.

There's a proven element of pitching that the more offerings that you can throw 10 percent of the time, for strikes, lowers your ERA. It just does. It beats the stuff metrics that we have. It's not a thing that Castillo does—four-seamer, sinker, change up, slider. It's pretty much just that. Sometimes no change up, sometimes just four-seamer/slider. And adding in that cutter could be one of those ways that he staves it off."

Adding a new pitch seems like an offseason adjustment rather than something we could see in-season on the fly, but it will be worth monitoring as we move forward.

With Raleigh banged up, the Mariners need all the help they can get.

First pitch is 1:10 p.m. PT.

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