The Arizona Diamondbacks host the San Francisco Giants for a three-game set, with the NL West rivals battling for a Wild Card spot in the final weeks of the season.
My Giants vs. Diamondbacks predictions target Arizona as the home favorite to open the series.
Read on for my MLB picks for September 15, with first pitch scheduled for 9:40 p.m. ET.
Giants vs Diamondbacks prediction
Giants vs Diamondbacks best bet: Diamondbacks moneyline (-130)
The San Francisco Giants and Arizona Diamondbacks meet for the second series in as many weeks, but this time the action shifts to Arizona.
San Francisco took the first two games of the series last week, but has since lost three of its previous four contests. On the flip side, Arizona has won three of its last four as it returns home.
Just half a game separates these two, but San Francisco is 37-37 on the road while Arizona is 38-34 at home. Furthermore, the Diamondbacks have a significant advantage on the mound tonight.
Kai-Wei Teng is getting the nod for the Giants. The righthander is 2-4 with 19 ER allowed in just 22 2/3 IP across six games (five starts).
Since throwing five shutout innings against the Nationals at home, he’s allowed 14 ER in 14 1/3 IP in his last four starts — that includes eight in 12 2/3 in three straight starts on the road.
Zac Gallen is having a down year for Arizona and was victimized by the long ball in San Francisco last week, but he’s been fairly consistent in the second half. Prior to last week’s start on the road, he allowed just 10 ER in 41 IP across his previous seven starts.
Even if Gallen falters, he should be able to outduel Teng in Arizona.
Giants vs Diamondbacks same-game parlay (SGP)
The Diamondbacks should have no problem getting on the board against Teng, and the Giants’ bullpen hasn’t been great recently either.
One area where Teng has been strong is in the strikeout category. He has 28 Ks in 22 2/3 frames, including 16 in 9 1/3 IP across his last two starts.
Giants vs Diamondbacks SGP
- Diamondbacks moneyline
- Over 9
- Kai-Wei Teng Over 4.5 strikeouts
Giants vs Diamondbacks odds
- Moneyline: San Francisco +110 | Arizona -130
- Run line: San Francisco +1.5 (-170) | Arizona -1.5 (+145)
- Over/Under: Over 9 (-120) | Under 9 (+100)
Giants vs Diamondbacks trend
The Arizona Diamondbacks have hit the team total Over in 28 of their last 40 games (+15.20 Units / 34% ROI). Find more MLB betting trends for Giants vs. Diamondbacks.
How to watch Giants vs Diamondbacks and game info
| Location | Chase Field, Phoenix, AZ |
| Date | Monday, September 15, 2025 |
| First pitch | 9:40 p.m. ET |
| TV | NBCSBA, DBACKS.tv |
| Giants starting pitcher | Kai-Wei Teng (2-4, 7.54 ERA) |
| Diamondbacks starting pitcher | Zac Gallen (11-14, 4.84 ERA) |
Giants vs Diamondbacks latest injuries
Giants vs Diamondbacks weather
Odds are correct at the time of publishing and are subject to change.
Not intended for use in MA.
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