Cardinals vs. Mariners prediction: Seattle favored to win Tuesday's MLB matchup [9/9/2025]

The Seattle Mariners and St. Louis Cardinals are scheduled to meet in MLB action at T-Mobile Park on Tuesday, starting at 9:40PM ET.

George Kirby (8-7, 4.47 ERA) will start on the mound for the Mariners, while the Cardinals have opted for Matthew Liberatore (7-11, 4.15 ERA).

Based on updated simulation results, Dimers' advanced MLB model predicts the Mariners as the most likely winner of today's game.

For expanded analysis of Tuesday's matchup, including best bets and picks, visit our interactive Cardinals vs. Mariners predictions page.

Mariners vs. Cardinals prediction: Who will win, cover the run line?

Using trusted machine learning and statistical analysis, we have simulated the outcome of Tuesday's MLB game between the Cardinals and Mariners 10,000 times as part of our MLB predictions coverage.

Our famous predictive model currently gives the Mariners a 63% chance of defeating the Cardinals.

According to our model, the Cardinals (+1.5) have a 55% chance of covering the run line, while the over/under total of 7.5 runs has a 55% chance of going over.

Cardinals vs. Mariners odds [9/9/2025]

We have researched the best MLB odds in America for this game, which are listed here:

Bet Type	Cardinals	Mariners
Run Line	+1.5 (-125)	-1.5 (+105)
Moneyline	+170	-190
Total	o7.5 (-110)	u7.5 (-105)

All odds are correct at the time of publication and are subject to change.

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Cardinals vs. Mariners picks and best bets

Our model's strongest edge in today's Cardinals vs. Mariners matchup is on the run line.

Our expert predictions, aligned with the best odds, reveal the best MLB picks and MLB best bets for every game throughout the season.

Unlimited access to our full suite of picks, including this one, is available via Dimers Pro.

Calling Our Shot's free ⚾️ picks

Calling Our Shot produces daily MLB betting content, including the predictions featured below.

Cardinals vs. Mariners game-day updates and essential details

Tuesday's MLB matchup between the Mariners and Cardinals at T-Mobile Park is scheduled to commence at 9:40PM ET.

• Who: St. Louis Cardinals vs. Seattle Mariners
• Date: Tuesday, September 9, 2025
• Time: 9:40PM ET/6:40PM PT
• Venue: T-Mobile Park

Dimers' comprehensive preview of Tuesday's Cardinals vs. Mariners matchup includes our prediction, picks and the latest betting odds.

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Conclusion

We predict the Mariners, with a 63% win probability, will likely beat the Cardinals on Tuesday.

AI and automation have enhanced this article to quickly deliver accurate Cardinals vs. Mariners insights, with human oversight ensuring high editorial quality. Our predictions are based on the latest data to help you make informed decisions. For additional resources and advice on responsible gambling, please call 1-800-GAMBLER.

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