Seattle Mariners starting pitcher Luis Castillo smiles during a game against the Tampa Bay Rays on Aug. 8 at T-Mobile Park. Steven Bisig-Imagn Images

Seattle Mariners Veteran Pitcher Leads Franchise in Astonishing Historical Category

Originally posted on Seattle Mariners on SI
By Teren Kowatsch | Last updated Aug 12, 2025 1:37 PM ET

The Seattle Mariners starting rotation has been hit big with the injury bug this season. Three of the team's five starting pitchers going into this season have had four respective stints on the injured list.

Logan Gilbert and George Kirby have started to return to midseason form after their ailments, and Bryce Miller will make his third rehab start with the Triple-A Tacoma Rainiers on Wednesday. Miller is currently on his second IL stint due to right elbow inflammation.

Amidst all that turmoil, veteran pitcher Luis Castllo and third-year starter Bryan Woo have anchored the rotation. Both pitchers have maintained their health. Castillo has made 24 starts this year and Woo has 23 entering Tuesday.

Luis Castillo, Crazy 97mph Two Seamer.

22 Inches of Run.

He definitely seemed impressed with himself. pic.twitter.com/GL6i1XD36U
— Rob Friedman (@PitchingNinja) May 20, 2025

Castillo's steadiness has earned him the top spot on an incredible list of franchise greats, which includes a National Baseball Hall of Famer.

Castillo passed 500 innings pitched with Seattle this season. According to a post on "X" from Mariners PR, the ninth-year pitcher leads the franchise in ERA for pitchers who have reached that mark.

Castillo has a 3.38 ERA among franchise pitchers with at least 500 innings pitched, which leads National Baseball Hall of Famer Randy Johnson (3.42), Mariners Hall of Famer Felix Hernandez (3.42), Hisashi Iwakuma (3.42), James Paxton (3.42) and Castillo's current teammates Kirby (3.51) and Gilbert (3.58).

Mariners All-Time ERA leaders (min. 500 IP):

1️⃣ LUIS CASTILLO (3.38)
T2️⃣ Randy Johnson (3.42)
Félix Hernández (3.42)
Hisashi Iwakuma (3.42)
James Paxton (3.42)
6️⃣ GEORGE KIRBY (3.51)
7️⃣ LOGAN GILBERT (3.58)
— Mariners PR (@MarinersPR) August 11, 2025

Entering Tuesday, Castillo has a 3.19 ERA with 120 strikeouts across 138.1 innings pitched in his 24 starts. That mark would be his best ERA in a single season since 2022 — the year Seattle acquired him in a trade from the Cincinnati Reds.

This article first appeared on Seattle Mariners on SI and was syndicated with permission.

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