The Seattle Mariners travel to George M. Steinbrenner Field on Monday as heavy favourites against a Tampa Bay Rays side fighting to stay relevant in the playoff picture.
With Luis Castillo taking the mound for Seattle and Shane Baz countering for Tampa Bay, this matchup pits two teams heading in opposite directions as the regular season winds down.
The Mariners' superior record at 72-62 has them installed as -275 moneyline favourites, but the Rays have shown they can punch above their weight at home despite their 64-69 mark.
Tampa Bay Rays vs. Seattle Mariners prediction: who will win?
For tonight's Tampa Bay Rays vs Seattle Mariners matchup, our predictive model gives the Rays a 75% chance of defeating the Mariners.
Tampa Bay Rays: 75% win probability
- Strong offensive production averaging 4.49 runs per game (611 runs in 136 games)
- Solid defensive metrics allowing just 4.15 runs per game (564 runs allowed)
- Recent momentum with three wins in their last five games (WWWLL)
Seattle Mariners: 25% win probability
- Inconsistent recent form with just two wins in last five (WLLWL)
- Below-average run differential at +25 (627 scored, 602 allowed)
- Road struggles as evidenced by their .533 winning percentage despite decent talent
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.
Rays vs. Mariners Odds
These are the best MLB odds we found across major U.S. sportsbooks for this game.
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Tampa Bay Rays vs. Seattle Mariners preview
The Mariners roll into Tampa Bay as heavy favorites at -275, carrying a solid 72-62 record but facing questions about their recent offensive struggles that have them sitting 11th in scoring at just 4.6 runs per game.
Luis Castillo takes the mound for Seattle with his reliable 3.58 career ERA and strong strikeout numbers, though he'll be tested by a Rays lineup that's been more productive than expected despite their disappointing 64-69 record.
Shane Baz counters for Tampa Bay with his 4.38 ERA, and while the young right-hander has shown flashes of brilliance, consistency remains an issue as the Rays look to play spoiler in what's essentially a must-win situation.
Seattle's pitching staff has been middle-of-the-pack this season, ranking 17th with a 3.97 team ERA, while their bullpen has struggled mightily with just a 62.5% save rate that could prove costly in tight games.
The Rays have actually been the better defensive club, ranking 5th in defensive efficiency compared to Seattle's 12th-place mark, which could be the difference-maker in what projects as a low-scoring affair.
With Tampa Bay getting plus-money at home and Seattle carrying the weight of heavy expectations, this line feels inflated for a Mariners team that's been inconsistent down the stretch.
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