Breaking Down the Seattle Mariners' 2024 Starting Rotation Ahead of Opening Day

The Seattle Mariners, who went 88-74 last season and missed the playoffs by 1.0 game, appear to have one of the best rotations in all of baseball entering 2024. That said, the depth has been tested early with the injury to Bryan Woo. Here's how Seattle stacks up entering 2024.
Texas Rangers v Seattle Mariners
Texas Rangers v Seattle Mariners / Steph Chambers/GettyImages
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The 2024 MLB regular season is about to begin, and that means it's time for every club to lock down its top five starting pitchers.

The Seattle Mariners are looking for a return trip to the playoffs after missing them in 2023. After a great 2022 season that saw them win a playoff series in the Wild Card round, the M's went 88-74 and missed a playoff spot in the final weekend of the regular season. If Seattle is going to get back this year, they'll need to rely on the strength of their starting pitching, which is thought to be among the best group in all of baseball.

Here is a quick preview of how Seattle's starting pitching will look in 2024:

1. Luis Castillo, RHP
2023 Stats: 14-9, 3.34 ERA, 1.10 WHIP, 10.01 K/9, 3.4 WAR
2024 Projections: 12-10, 3.65 ERA

Castillo gets the Opening Day start for the second consecutive year with Seattle. Since being acquired at the 2022 trade deadline, he's been one of the pitchers in the American League and is coming off an All-Star season.

2. George Kirby, RHP
2023 Stats: 13-10, 3.35 ERA, 1.04 WHIP, 8.12 K/9, 4.4 WAR
2024 Projections: 12-10, 3.63 ERA

One of the elite strike-throwers in all of baseball, Kirby is also coming off an All-Star season that saw him take the mound at T-Mobile Park in the Midsummer Classic. He assumes the No. 2 spot in the rotation this year.

3. Logan Gilbert, RHP
2023 Stats: 13-7. 3.73 ERA, 1.08 WHIP, 8.92 K/9, 3.2 WAR
2024 Projections: 12-11, 3.88 ERA

Seemingly overshadowed by Castillo and Kirby, Gilbert remains one of the most durable pitchers in the American League, having thrown greater than 185 innings in each of the last two years. He's continuing to develop a splitter which help him play off his fastball.

4. Bryce Miller, RHP
2023 Stats: 8-7, 4.32 ERA, 1.14 WHIP, 8.15 K/9, 1.9 WAR
2024 Projections: 9-9, 4.32 ERA

Making his Major League debut last season, Miller is a huge reason why the Mariners stayed in contention as long as they did. With a mid-90s fastball and a new-found splitter, he has multiple weapons to play with.

5. Emerson Hancock*, RHP
2023 Stats: 0-0, 4.50 ERA, 1.33 WHIP, 4.50 K/9, 0.2 WAR
2024 Projections: 5-6, 4.70 ERA

Hancock enters the early-season rotation because of the injury to Bryan Woo, who is expected to miss the first few weeks of the season with elbow inflammation.

All 2024 projections are compiled using FanGraphs' Steamer model.

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Brady Farkas


Brady Farkas is a baseball writer for Fastball on Sports Illustrated/FanNation and the host of 'The Payoff Pitch' podcast which can be found on Apple Podcasts and Spotify. Videos on baseball also posted to YouTube. Brady has spent nearly a decade in sports talk radio and is a graduate of Oswego State University. You can follow him on Twitter @WDEVRadioBrady.