Diamondbacks vs. Giants Prediction, Odds, Probable Pitchers and Prop Bets for Tuesday, Sept. 9

The Giants are favored at home on Tuesday.

San Francisco Giants third baseman Rafael Devers is a solid prop target on Sept. 9. / Ron Chenoy-Imagn Images

The Arizona Diamondbacks and San Francisco Giants are both in the mix for a wild card spot in the National League, but they’ll need to finish strong to get there.

San Francisco is three games back of the New York Mets while the D-Backs are 4.5 games of the Mets heading into Tuesday night’s matchup.

Zac Gallen (4.77 ERA) is looking to close a rough 2025 season on a high note for Arizona, and he’ll take on lefty Robbie Ray (3.31 ERA) in San Francisco.

Ray has pitched well in 2025, leading the Giants to a 21-8 record in his 29 appearances. As a result, the best betting sites have set San Francisco as a home favorite in this NL West battle.

Let’s dive into the odds, my favorite prop bet and a prediction for this battle between playoff hopefuls. 

Diamondbacks vs. Giants Odds, Run Line and Total

Odds via DraftKings Sportsbook

Run Line

• Diamondbacks +1.5 (-185)
• Giants -1.5 (+151)

Moneyline

• Diamondbacks: +119
• Giants: -145

Total

• 7.5 (Over -106/Under -115)

Diamondbacks vs. Giants Probable Pitchers

• Arizona: Zac Gallen (11-13, 4.77 ERA)
• San Francisco: Robbie Ray (10-6, 3.31 ERA)

Diamondbacks vs. Giants How to Watch

• Date: Tuesday, Sept. 9
• Time: 9:45 p.m. EST
• Venue: Oracle Park
• How to Watch (TV): NBCS-BA, ARID
• Diamondbacks record: 72-73
• Giants record: 73-71

Diamondbacks vs. Giants Best MLB Prop Bets

Giants Best MLB Prop Bet

• Rafael Devers to Hit a Home Run (+425)

Earlier today, I shared in SI Betting’s best home run picks – Daily Dinger – why I’d bet on Devers to leave the yard against Arizona: 

San Francisco Giants star Rafael Devers has been red hot as of late, hitting .346 with six home runs over the last two weeks, pushing him to 31 homers in the 2025 season.

On Tuesday, he’ll take on Arizona Diamondbacks righty Zac Gallen, who has had a down 2025 season. Gallen has given up 26 home runs in 29 appearances while posting a 4.77 ERA, and he’s struggled in limited matchups with Devers.

The Giants star is 2-for-4 with a double and two walks in his career against Gallen, and I think he’s a great bet to leave the yard in this one. Against right-handed pitching this season, Devers is hitting .267 with a .916 OPS and 22 home runs. 

Diamondbacks vs. Giants Prediction and Pick

After a rough first few months, Gallen has turned things around since August, posting a 2.20 ERA over his last seven starts, leading the D-Backs to a 5-2 record during that time.

Ray has led the Giants to a 21-8 record and posted a 3.31 ERA in 2025 But, he has not fared nearly as well as of late. The lefty has a 4.54 ERA over his last seven starts (since Aug. 1). Still, the Giants have won six of those games.

I actually lean with the UNDER in this matchup since Gallen is starting to turn things around. San Francisco has been too good in Ray’s starts to bet against it at home, but if Ray pitches a little better, this should be a low-scoring affair. 

Plus, the Giants have the No. 2 bullpen ERA (3.32) in MLB this season. 

Pick: UNDER 7.5 (-115 at DraftKings)

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Odds refresh periodically and are subject to change.

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