Nationals vs. Cardinals prediction: St. Louis favored to win Friday's MLB matchup [9/18/2026]

The St. Louis Cardinals will take on the Washington Nationals, in what is expected to be a tight MLB game, at Busch Stadium on Friday, starting at 8:15 PM ET.

The Cardinals will start Kyle Leahy (10-4, 3.33 ERA), up against Cade Cavalli (12-5, 3.12 ERA) for the Nationals.

Dimers' advanced MLB model gives the Cardinals a slight edge with a 52.0% win probability over the Nationals.

This article offers a complete Nationals vs. Cardinals prediction, including best bets and picks.

Nationals vs. Cardinals prediction and odds

Using innovative machine learning and data analysis, we have re-simulated the result of Friday's MLB matchup between the Nationals and Cardinals, forming part of our MLB predictions coverage.

Our famous predictive model currently gives the Cardinals a 52.0% chance of defeating the Nationals. According to our model, the Cardinals (+1.5) have a 64.3% chance of covering the run line, while the 7.5-run over/under has a 56.3% chance of going over.

Latest betting odds

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

• Run Line: Nationals -1.5 (+167) / Cardinals +1.5 (-170)
• Moneyline: Nationals -104, Cardinals +102
• Total: Over/Under 7.5 (-104/+104)

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

Model picks and best bet

After matching our probabilities against the best current odds, we can reveal our picks for each of the major markets in this matchup. Plus, find our best bet for the game below:

• Run line: Cardinals +1.5 @ 63¢ via Novig
• Moneyline: Cardinals @ 50¢ via Novig
• Total: Over 7.5 @ 51¢ via Novig

According to our MLB best bets, the top play to make on this game is Over 7.5 total runs.

These picks are based on our probabilities matched against the implied probabilities from the current available odds.

Game info & first pitch details

Friday's MLB matchup between the Cardinals and Nationals at Busch Stadium is scheduled to start at 8:15 PM ET.

• Who: Washington Nationals vs. St. Louis Cardinals
• Date: Friday, September 18, 2026
• Time: 8:15 PM ET/5:15PM PT
• Venue: Busch Stadium

Conclusion

We predict the Cardinals, with a 52.0% win probability, will likely beat the Nationals in Friday's MLB matchup.

Additional tools and information for betting safely can be found in our Responsible Gambling hub.

This article's predictions and probabilities are generated by Dimers' proprietary MLB prediction model. Our editorial team reviews the resulting content for accuracy and presentation before publication.