The Mariners have been holding player plan meetings after on-field work has been done the last couple of weeks. Every player has one of these meetings, and the work that goes into putting them together is extensive with coaches, analysts, trainers and high performance staff coming together to find a way to make each player better.

Who’s the Mariners’ most important player besides Julio Rodríguez?

With a young player, the plans can be very detailed as there is plenty of room to grow. What does the plan look like for an accomplished veteran like Luis Castillo, who makes his first spring training start Tuesday against the Guardians?

“I think with him, he did some things differently with us than he had done previously,” said manager Scott Servais about Castillo, who joined the Mariners ahead of the trade deadline last July. “It’s more pitch-usage, strategy type stuff than the fundamental things you might be talking about with a younger player.”

The Mariners ran the numbers on Castillo’s stuff and outcomes, and as a result asked him to throw his slider more to left-handed hitters rather than throw so much of his changeup in that situation.

“He came into the league, the fastball-changeup guy – and a dominant changeup,” Servais noted. “And of course, hitters make adjustments, they know that’s a big part of his game, (the changeup) at the bottom of strike zone. So what we saw last year is a lot of his strikeouts came from the fastball that was elevated from that slot, along with the slider. It’s a really important pitch getting back into counts against left-handed hitters. Those are things we talked about with him, ‘Let’s continue to do this. They’ll be focused on where you’re trying to target your slider, and where that needs to go in certain counts.'”

The catchers play a huge role in the execution of pitcher’s player plans. According to Servais, Castillo does not shake his catchers off very often.

“We’ve got guys that do a really nice job of listening to that information, and then figuring out a way how to work that into what he’s doing,” he explained. “I think it’s one of Cal (Raleigh)’s biggest strengths and (Tom) Murphy’s as well – they take the info, they can put it in play in the game. And (with Castillo), ‘You want me to throw more sliders? OK, I’ll throw more sliders.’ Just happens to be a really good slider. ‘Want me to throw more fastballs up? I’ll throw 100 (mph).’ It works. there’s a lot you can do with that talent.”

Lineup!

Mariners vs. Cleveland Guardians, 12:10 p.m.
(Game airing on tape delay at 7 p.m. on Seattle Sports)

Kolten Wong, 2B
Teoscar Hernández, RF
Ty France, 1B
Eugenio Suárez, 3B
Cal Raleigh, C
J.P. Crawford, SS
Cade Marlowe, LF
Kole Calhoun, DH
Leonys Martín, CF

Luis Castillo, RHP

2023 Mariners spring training radio schedule on Seattle Sports

Mariners notes

• All eyes will be on pitching prospect Bryce Miller as he should follow Castillo in Tuesday’s game. Other pitchers on the roster today include Penn Murfee, Diego Castillo, Trevor Gott and Riley O’Brien.

• PitchCom is no longer a one-way communication tool. Pitchers are now permitted to carry the transmitters, giving them the ability to call their own pitches to catchers rather than vice versa. We’ve seen a couple of opposing pitchers with the transmitters but to date a Mariners pitcher has not used one.

Mariners Notebook: Julio Rodríguez fine, undeterred after wall crash

Follow @shannondrayer