Diamondbacks vs. Padres Prediction, Pick for Thursday’s MLB Game

First pitch for the Arizona Diamondbacks vs. San Diego Padres game is set for 9:40 p.m. ET on Thursday, July 9, with the Padres entering as home favorites in this NL West showdown, returning a 1.75x payout if they win, via PrizePicks.

Today’s game is the fourth and final game of the Diamondbacks-Padres series between two division rivals. The Padres have won two of the first three games and will go for the series victory tonight, while the Dbacks will look to knot it up. 

Below, we'll break down our Diamondbacks vs. Padres prediction and picks for tonight's MLB game, including the run line, over/under, and top MLB player picks.

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Diamondbacks vs. Padres Prediction, Favorite to Win, Over/Under – Thursday, July 9

The Diamondbacks will send Merrill Kelly (5.29 xFIP in 89.2 innings) to the bump tonight. Kelly is in the midst of his worst season as a professional, with his 7.82 xERA being around 2.5 runs worse than his previous worst xERA, which came back in 2019 (5.33). 

Arizona currently sits at 45-47 and 15 games behind the Los Angeles Dodgers for first place in the division. The Diamondbacks will need Kelly to be much better than he has been if they hope to get on equal footing with the Padres, record-wise, who sit just one game ahead of them at 46-46.

The Padres were probably hoping to compete with the Dodgers for first place in the NL West this season, but instead they find themselves in a close race with the Diamondbacks for second. 

They send Griffin Canning (4.71 xFIP) to the mound tonight. He has battled walks all season, with his 5.29 BB/9 a career high for the 30-year-old righty. He faced a similar-looking Arizona lineup last season as a member of the New York Mets, where he held them to 1 run over 5 innings of work with 6 strikeouts.

Diamondbacks vs. Padres Winner Payout, Over/Under – Thursday, July 9

The Padres enter Thursday’s game as home favorites against the Diamondbacks, returning a 1.75x payout if they win outright, via PrizePicks Team Picks.

Here are the full payouts for the Diamondbacks vs. Padres game on PrizePicks.

• Spread: San Diego Padres -1.5 (2.5x payout)
• Over/Under: 8.5 (1.75x payout on Over)
• Game Winner Payout: Diamondbacks 2x | Padres 1.75x

Team Picks data is live at the time of writing and is subject to change.

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Diamondbacks vs. Padres Prediction on Winner – July 9, 2026

Here are the key game stats and trends behind our Diamondbacks vs. Padres prediction on the winner for Thursday, July 9, in this NL West division showdown.

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Unless otherwise noted, data used in this article is from Baseball Savant or FanGraphs.

• Despite San Diego’s .500 record, the Padres have been one of the best teams in baseball against the spread (ATS). They have a 50-42 ATS record (54.4%), tied for the sixth-best covering percentage in the league.
• The Padres have underperformed their talent level in the batter's box this season (28th in season-long wRC+), but they have turned it on recently, ranking 9th in wRC+ (114) over the last 14 days.
• The Diamondbacks have been equally as bad on a season-long level (29th in season-long wRC+), but they have not turned things around in recent weeks, with their wRC+ of 78 ranking fourth-worst in baseball over the last 14 days.
• I mentioned above that Canning has struggled with walks this season, but the Diamondbacks may not be well-suited to take advantage of that weakness, as they rank just 23rd in MLB in walk rate (8.4%).
• San Diego also has a much better bullpen than the Diamondbacks; they own a 3.98 xFIP this season (7th) compared to the Diamondbacks 4.24 xFIP (14th).
• The Arizona pen also owns a .277 BABIP compared to the Padres' .296 BABIP.

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Diamondbacks vs. Padres Picks for MLB Today – Thursday, July 9

Here are the top Diamondbacks vs. Padres picks to target on PrizePicks for Thursday, July 9. Today’s MLB picks today include Merrill Kelly and Griffin Canning.

Diamondbacks P Merrill Kelly vs. Padres – 4 Strikeouts

• Kelly is sporting a 5.5 K/9 this season, by far the worst strikeout rate he has ever had in a single season.
• His 9.3% swinging strike rate is also the second-lowest of his career, with only his 8.8% rate in 2021 being lower.
• On the road, Kelly has been even worse in the strikeout department with an unbelievably poor K/9 of 4 compared to his 7.99 K/9 at home.
• The Padres' offense is striking out at a 22.8% clip this season, but has been more selective at the plate recently, lowering that rate to 20.9% over the last 14 days.
• Kelly has not been a model of success in surpassing his projections, as he has had four or fewer strikeouts in nine of his last ten starts (90%).

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Padres P Griffin Canning vs. Diamondbacks – 4 Strikeouts

• Canning rarely pitches over five innings and 80 pitches, indicating that the Padres do not want lineups seeing him the third time through, and also limiting his strikeout upside.
• Another thing limiting his K upside is the matchup tonight against a Diamondbacks team that is striking out at just a 19.4% clip this season, second-fewest in baseball.
• Over the last 14 days, the Diamondbacks have been striking out just 18.9% of the time.
• His 8.82 K/9 is decent, but it is backed by peripherals suggesting it could be due for a negative regression.
• His 9.9% swinging strike rate has been serviceable, but only if he is consistently pounding the zone, which he is not. 
• His 54.6% first strike rate is well below the league average of roughly 60%. If he is consistently falling behind the high-contact Diamondbacks hitters, it could be difficult to catch up and get punch outs.

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Make Diamondbacks vs. Padres Picks on PrizePicks

The Padres beat the Diamondbacks 10-4 yesterday and can go for the series victory with a win tonight. Meanwhile, the Diamondbacks can leave San Diego tonight with both teams at 46-47 and tied for 2nd in the NL West if they can find a W in Southern California.  Diamondbacks vs. Padres is just one of the games for you to get all your action on on PrizePicks.

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