The Seattle Mariners face a crucial late-season test at T-Mobile Park on Wednesday against the struggling Colorado Rockies, with Seattle's playoff hopes hanging in the balance despite being heavy favourites at -182.
Luis Castillo takes the mound for the Mariners with his stellar 3.57 ERA as they look to capitalise on Colorado's league-worst pitching staff that has allowed nearly six runs per game.
With the Rockies sitting at a dismal 43-113 record and featuring one of baseball's weakest rotations, this matchup presents an interesting betting angle as experts debate whether the massive spread offers any value.
Seattle Mariners vs. Colorado Rockies prediction: who will win?
For tonight's Seattle Mariners vs Colorado Rockies matchup, our predictive model gives the Mariners a 51% chance of defeating the Rockies.
Seattle Mariners: 51% win probability
- Strong offensive production averaging 4.7 runs per game (745 runs in 157 games)
- Solid pitching staff allowing just 4.3 runs per game (676 runs allowed)
- Excellent recent form riding a five-game winning streak (WWWWW)
Colorado Rockies: 49% win probability
- Worst record in baseball at 43-114 (.274 winning percentage)
- Terrible pitching staff allowing 6.3 runs per game (992 runs allowed in 157 games)
- Poor recent form with inconsistent play (LWLWL in last five games)
At Sporting Post, our custom prediction model blends insights from leading MLB analysts to give you a clear edge.
Instead of sorting through endless opinions, we streamline expert picks, advanced team metrics, and market trends into one place. Our AI tracks top sources and assigns a confidence score to each prediction. These are averaged into a win probability that reflects the expert consensus. It gives you a data-backed view of what the sharpest minds in MLB expect.
Mariners vs. Rockies Odds
These are the best MLB odds we found across major U.S. sportsbooks for this game.
Odds are based on the latest data at publication and are subject to real-time updates.
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Seattle Mariners vs. Colorado Rockies preview
The Mariners find themselves in a prime position to showcase their playoff credentials against a Colorado team that has endured one of the most brutal seasons in recent memory, sitting at 43-113 and dead last in nearly every meaningful pitching category.
Luis Castillo takes the mound for Seattle with his 3.57 career ERA and solid 83-84 record, facing off against rookie Tanner Gordon, who has struggled mightily with a 6.87 ERA and 6-13 record in his debut campaign.
While the Rockies have managed just 3.7 runs per game this season, ranking 29th in the majors, the Mariners have been far more productive offensively at 4.75 runs per contest despite their own inconsistencies at the plate.
The pitching disparity tells the real story here, with Colorado's staff posting a ghastly 5.99 ERA that ranks dead last in baseball, while Seattle's 3.89 mark sits comfortably in the middle of the pack.
Gordon has been particularly vulnerable on the road, surrendering 12.0 hits per nine innings, which could spell trouble against a Mariners lineup that has shown flashes of power with 230 home runs this season.
For Seattle, this represents exactly the type of matchup they need to build momentum, especially at home where they can rely on Castillo's experience and their superior bullpen depth to close out what should be a manageable opponent.
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