Diamondbacks vs. Cardinals Prediction, Odds, Probable Pitchers and Prop Bets for Friday, May 23

Iain MacMillan | May 23, 2025

The Cardinals are home underdogs to the Diamondbacks on Friday night. / Peter Aiken-Imagn Images

The Arizona Diamondbacks have a 26-24 record this MLB season, but that's good for just fourth in the NL West, five games back from the first place Los Angeles Dodgers.

Meanwhile, the St. Louis Cardinals are 27-23, just one game better from the Diamondbacks, but are in second place in the NL Central, only three games back from the Chicago Cubs.

This could be a pivotal series for both teams. Let's take a look at the odds and my best bets for tonight's series-opener.

Diamondbacks vs. Cardinals Odds, Run Line, and Total

Odds via BetMGM Sportsbook

Run Line

• Diamondbacks -1.5 (+135)
• Cardinals +1.5 (-165)

Moneyline

• Diamondbacks -130
• Cardinals +105

Total

• 8.5 (Over -118/Under -102)

Diamondbacks vs. Cardinals How to Watch

• Date: Friday, May 23
• Game Time: 8:15 PM EST
• Venue: Busch Stadium
• How to Watch (TV): Apple TV+
• Diamondbacks Record: 26-24
• Cardinals Record: 27-23

Diamondbacks vs. Cardinals Probable Pitchers

• Arizona: Zac Gallen, RHP (3-5, 5.14 ERA)
• St. Louis: Miles Mikolas, RHP (3-2, 3.77 ERA)

Diamondbacks vs. Cardinals Best Prop Bet

• Brendan Donovan Home Run (+900)

In today's edition of Daily Dinger, I broke down why I'm betting on Brendan Donovan of the Cardinals to hit a home run:

Zac Gallen of the Diamondbacks has struggled this season, which has led to allowing 1.6 home runs per nine innings pitched. The Diamondbacks' bullpen also has the second-highest home run rate amongst all bullpens at 1.4 per nine innings. That means the St. Louis Cardinals are going to have plenty of opportunities to hit dingers tonight. The player I'm targeting to go deep tonight is Brendan Donovan, who, despite only having three home runs so far this season, leads the team amongst all players who have played 20+ games in slugging percentage at .455.

Diamondbacks vs. Cardinals Prediction and Pick

In today's Walk-Off Wagers, I wrote about why I'm betting on the OVER in tonight's National League matchup:

To cap off our night, we have a great game between two hot offenses and two not-so-great starting pitchers. The Diamondbacks and Cardinals rank fourth and eighth respectively in OPS this season, while combining for 9.92 runs per game. I see no reason why they can't reach a combined nine runs again tonight as neither team has their ace on the mound.

Zac Gallen (5.14 ERA) of the Diamondbacks has struggled this season, and he has allowed a combined 10 earned runs in his last two starts. Miles Mikolas has had a much better season with an ERA of 3.77, but based on a sudden improvement after a 2023 season with a 4.78 ERA and a 2024 season with a 5.35 ERA, I wouldn't be surprised to see some regression from the Cardinals' arm.

Neither bullpen stands out either. The Cardinals rank 15th in bullpen ERA (3.86) and the Diamondbacks rank 27th (5.28), so don't be surprised to see some late-inning runs tonight.

Pick: OVER 8.5 (-110)

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You can check out all of Iain's bets here!