Royals vs. Mariners Prediction: Seattle Predicted to Win Monday's MLB Matchup [6/30/2025]

MLB action continues on Monday at 9:40PM ET as the Kansas City Royals square off with the Seattle Mariners at T-Mobile Park.

The Mariners will send George Kirby (1-4, 5.40 ERA) to the mound, pitting him against Michael Wacha (4-7, 3.33 ERA) for the Royals.

Based on updated simulations, Dimers' proven MLB model (see Dimers Pro for full access) projects the Mariners as the most likely winner of today's game.

"Our team has utilized the latest data to simulate Monday's Royals-Mariners game 10,000 times," said Dimers' Chief Content Officer, Nick Slade.

"Incorporating recent updates and thousands of additional inputs, our prediction shows the Mariners are likely to win, with a probability of 57%, compared to the Royals' 43%."

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

Mariners vs. Royals Prediction: Who Will Win, Cover the Run Line?

Using trusted machine learning and data analysis, we have simulated the outcome of Monday's MLB matchup between the Royals and Mariners 10,000 times as part of our MLB predictions coverage.

Our famous predictive model currently gives the Mariners a 57% chance of beating the Royals.

According to our model, the Royals (+1.5) have a 61% chance of covering the run line, while the 7-run over/under has a 55% chance of going over.

Royals vs. Mariners Odds [6/30/2025]

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

Bet Type	Royals	Mariners
Run Line	+1.5 (-155)	-1.5 (+134)
Moneyline	+138	-158
Total	o7 (-119)	u7 (+100)

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

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Royals vs. Mariners Picks and Best Bets

Our model's strongest edge in today's Royals vs. Mariners matchup is on the moneyline.

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

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

Calling Our Shot's Free MLB Picks

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Royals vs. Mariners Game-Day Updates and Essential Details

Monday's MLB action between the Mariners and Royals at T-Mobile Park is scheduled to start at 9:40PM ET.

• Who: Kansas City Royals vs. Seattle Mariners
• Date: Monday, June 30, 2025
• Time: 9:40PM ET/6:40PM PT
• Venue: T-Mobile Park

Dimers.com's in-depth preview of Monday's Royals vs. Mariners matchup includes our prediction, picks and the latest betting odds.

Before making any Royals vs. Mariners picks, be sure to check out the latest MLB predictions and betting advice from Dimers Pro.

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Conclusion

We predict the Mariners, with a 57% win probability, will likely beat the Royals on Monday.

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

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