San Francisco Giants vs Arizona Diamondbacks Prediction – 9/15/2025
The San Francisco Giants will visit the Arizona Diamondbacks on Monday night. This game features two clubs with postseason hopes, as both teams are still in the thick of the NL Wild Card race. Both teams will be looking for a win to start this series off on the right foot and to move ahead of the other in the Wild Card standings. Here, I determine which team I think will get the job done as I make my Giants vs Diamondbacks prediction for Monday.
Our Giants vs Diamondbacks Pick
- Pick: Diamondbacks moneyline
- Confidence: ★★★☆☆
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Game Snapshot
- Matchup: San Francisco Giants vs Arizona Diamondbacks
- Date & Time: Tuesday, September 16, 2025, 9:40 p.m. ET
- Starting Pitchers: Kai-Wei Teng vs Zac Gallen
- Stadium: Chase Field, Phoenix, AZ
- Broadcast: MLB.TV
Key Storylines
- The Giants enter Monday’s play 1.5 games back of the New York Mets for the final NL Wild Card spot. Arizona is two games back for that Wild Card position. Both teams will be desperate for a win to move closer to the Mets tonight.
- The Giants struggled over the weekend against the NL West leading Dodgers. They will need to figure out how to respond in a hurry to avoid another devastating loss tonight.
- Both teams are sending starting pitchers to the mound who have struggled at times this year. The performances of Kai-Wei Teng and Zac Gallen will be vital for their team’s chances of winning.
Pitching Matchup
- Kai-Wei Teng enters this game with a 2-4 record and a concerning 7.54 ERA. His 1.76 WHIP needs to come down if the Giants are going to avoid losses in his starts down the stretch this year.
- Zac Gallen gets the start for the Diamondbacks tonight. He is 11-14 with a 4.84 ERA on the year. Gallen is capable of much better than he has shown this season. Now would be the perfect time for him to showcase what he can do.
Recent Team Streaks
- The Giants have lost two straight games and three of their last four.
- Arizona has won two straight games and three of their last four heading into this huge matchup.
Best Player Props
| Player | Prop Type | Pick |
|---|---|---|
| Zac Gallen | Strikeouts | Over 5.5 |
| Kai-Wei Teng | Strikeouts | Under 3.5 |
| Corbin Carroll | Total Bases | Over 1.5 |
| Geraldo Perdomo | Home Run | Over 0.5 |
Betting Trends & H2H
- The season series between these teams is tied 5-5.
- San Francisco is 37-37 on the road this year.
- Arizona is 38-34 in their home games in 2025.
Giants vs Diamondbacks Model Projection
Score Projection: Giants 3 – Diamondbacks 5
Win Probability: Giants 44%, Diamondbacks 56%
Final Thoughts
Neither team has a convincing starting pitching situation to rely on in this game. But I do think that the ceiling for Zac Gallen is significantly higher than that of Kai-Wei Teng for the Giants. I’ll take Arizona to get a huge win at home to help their chances in the NL Wild Card race at the expense of their division rivals.
