Astros vs. Diamondbacks Prediction: Arizona Predicted to Win Monday's MLB Matchup [7/21/2025]

The Arizona Diamondbacks will face the Houston Astros in MLB action at Chase Field on Monday, starting at 9:40PM ET.

Zac Gallen (7-10, 5.40 ERA) will be on the bump for the Diamondbacks, while the Astros have opted for Colton Gordon (3-2, 4.67 ERA).

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

For a closer look at Monday's matchup, including best bets and picks, visit our interactive Astros vs. Diamondbacks predictions page.

Diamondbacks vs. Astros Prediction: Who Will Win, Cover the Run Line?

Using powerful machine learning and statistical analysis, we have simulated the outcome of Monday's MLB matchup between the Astros and Diamondbacks 10,000 times as part of our MLB predictions coverage.

Our leading predictive model currently gives the Diamondbacks a 58% chance of beating the Astros.

According to our model, the Astros (+1.5) have a 61% chance of covering the run line, while the over/under total of 9 runs has a 52% chance of staying under.

Astros vs. Diamondbacks Odds [7/21/2025]

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

Bet Type	Astros	Diamondbacks
Run Line	+1.5 (-166)	-1.5 (+145)
Moneyline	+120	-139
Total	o9 (-102)	u9 (-112)

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

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Astros vs. Diamondbacks Picks and Best Bets

Our model's biggest edge in today's Astros vs. Diamondbacks matchup is on the moneyline.

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 complete 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 latest free picks featured below.

Astros vs. Diamondbacks Game-Day Updates and Essential Details

Monday's MLB game between the Diamondbacks and Astros at Chase Field is scheduled to start at 9:40PM ET.

• Who: Houston Astros vs. Arizona Diamondbacks
• Date: Monday, July 21, 2025
• Time: 9:40PM ET/6:40PM PT
• Venue: Chase Field

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

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

Conclusion

We predict the Diamondbacks, with a 58% win probability, will likely beat the Astros on Monday.

AI and automation have enhanced this article to quickly deliver accurate Astros vs. Diamondbacks insights, with human oversight ensuring high editorial quality. Our predictions are sourced from 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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