Seattle Mariners Fantasy Baseball Sleepers, Breakouts, and Comeback Players
The Seattle Mariners' path to success comes from the strength of their pitching staff, which is loaded with high-upside arms.
Sleeper: Bryan Woo, Seattle Mariners
The progression of Woo last season was impressive, but I can’t dismiss his early season elbow issue that showed up again in a minor way in mid-June. His minor league resume shows more strikeout ability, but he did outperform this profile with his walk rate (2.8).
The depth of his arsenal projects well against righties and lefties. Interesting option in 2025 as an entire season of his arm should help in a big way in WHIP if he repeats his growth in command. With no negative elbow news in spring training, tee him up and dream big.
Comeback Player: Randy Arozarena, Seattle Mariners
Arozarena slipped to 92nd in FPGscore (-0.98) for hitters due to his glaring weakness in batting average and RBIs. Over his previous three seasons, he finished 35th (3.26), 19th (6.08), and 32nd (2.82). His one positive in 2024 was the rise in his average hit rate (1.775), suggesting over 30 home runs if repeated over 550 at-bats. The good outweighs the bad on his professional resume, making him a value this season. There is a good chance Arozarena hits one slot in the batting order from Julio Rodriguez, creating an upside opportunity in runs or RBIs. Let’s go with .265 with 85 runs, 25 home runs, 80 RBIs, and 25 stolen bases.
Value: Luis Castillo, Seattle Mariners
The Mariners starting pitchers added a split-finger pitch to their arsenal over the past few seasons. Based on the direction of Castillo’s changeup, a grip change or new pitch may be required to pump some life into his arm against left-handed batters. When his changeup was more relevant, he was a high-volume groundball pitcher. His change in approach led to more fly-balls (42.2% and 40.0%) over the past two seasons, compared to under 27.0% from 2019 to 2021.
From 2017 through 2021, Castillo had an elite changeup (.174 BAA and .275 SLG). I’ve highlighted his recent weakness, so the fantasy market must pay attention to his spring work in March to see if he does indeed upgrade his off-speed pitch in 2025. Do the time or face the crime of making a bad investment. Spring pitch mix update:
Breakout: Andes Munoz, Seattle Mariners
When reviewing Munoz’s 2024 resume, he falls short in saves while ranking lower in strikeouts (77) due to his innings pitched (59.1). Both areas can be corrected by natural game flow and chances in 2025. He battled two minor injuries last season – back in early June and elbow in September.
For a fantasy team looking to wait on the closer position, Munoz is one of the better value options to target. Seattle has great starting pitchers, creating many close games. Well within range of 40+ saves and over 100 strikeouts.
Breakout: Bryce Miller, Seattle Mariners
The next magical step in Miller’s game is a jump in strikeouts. The change to his split-finger pitch last season erased his weakness against left-handed batters while giving another swing-and-miss pitch.
He looks poised to push his way up the starting pitching ranks in 2025 while being mispriced in the early draft season in the high-stakes market. Only 10 starters were better than him last year based on my FPGscore (4.12) ratings, and at least half of those pitchers will be passed this year.
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With 20+ years of experience in the high-stakes fantasy market, I aim to research and compete at the highest level in baseball and football each season. I've contributed as a writer/analyst for Sports Draft Daily, ScoutPro, Scout Fantasy, Fulltime Fantasy, FFToolbox, and Sports Illustrated Fantasy. I'm honored to be in the National Fantasy Baseball Championship Hall of Fame. My drafting philosophy is risk-averse yet open to betting on potential game-changers. I approach player selection with a neutral perspective, acknowledging that fantasy sports are inherently unpredictable due to injuries, performance dips, and managerial decisions. My work focuses on these main areas: - Season-long fantasy baseball and football - BestBall Baseball and Football Events - Daily Fantasy Sports (DFS): DraftKings, FanDuel, and Underdog - Long Shot Player Prop Parlays for NFL I participate in various leagues and contests, including NFBC, NFFC, RTSports, FFPC, DraftKings, Underdog Fantasy, FanDuel, and FFWC, with the goal of leveraging my extensive experience and research for success in each game format. A fantasy follower can expect in-depth profiles of NFL and MLB players, along with season-long and weekly projections for each fantasy football season. In addition, I have many strategy articles to help develop fantasy players' learning curves.