Our Diamondbacks vs. Padres prediction finds Arizona fighting for its wild-card life on Friday night at Petco Park. San Diego is a -128 home favorite, Arizona sits at +107, and the total is 7.5. The Padres have already clinched a postseason berth, while the D-backs trail Philadelphia by two games with three to play. Below, we break down the pitching matchup, the market and our two best bets.
Last Updated: September 25, 2026
Arizona Diamondbacks vs. San Diego Padres — Game Info
| Where | Petco Park, San Diego, California |
| When | September 25 – 9:40 PM ET |
| TV | Padres.TV, DBACKS.TV |
Arizona Diamondbacks vs. San Diego Padres Betting Preview
The pitching matchup drives this price. Brandon Pfaadt starts for Arizona with a 7-3 record, a 3.72 ERA and a 1.17 WHIP over 128 1/3 innings. He has been better than that line suggests, posting a 2.99 ERA over 11 starts since July 23. He has also handled San Diego, allowing four earned runs in 14 2/3 innings across three outings this season. However, his last five starts produced a 4.80 ERA. Arizona also lifted him after 64 pitches in the fifth inning against the Yankees last Saturday.
Casey Mize takes the ball for the Padres, and his trend points the other way. He posted a 2.70 ERA in 16 starts with Detroit before the trade. Since arriving in San Diego, though, he owns a 6.64 ERA across nine starts with a 1.62 WHIP. His walk rate has climbed to 3.76 per nine innings, and he has allowed 2.21 home runs per nine. Over his last five outings, Mize has worked just 22 2/3 innings, with 16 earned runs and 10 walks. Arizona chased him after 3 1/3 innings and eight earned runs on Aug. 5. To his credit, he held the D-backs to one run over six innings with Detroit on March 31.
The Padres are 89-70, hold the top NL wild-card spot and are 49-29 at Petco Park. They have won eight of their last 10 games, scoring 60 runs in that span. San Diego also took two of three at Dodger Stadium this week, and our Padres vs. Dodgers prediction previewed Thursday’s finale. Arizona is 85-74 and riding a five-game winning streak. Still, its elimination number is two, and the season series between these clubs is tied 5-5.
The bullpens add another layer. San Diego’s relievers own a 3.46 ERA this season, compared with 3.91 for Arizona, per MLB’s official stats. However, Padres relievers covered 14 innings in the three games at Los Angeles. Mason Miller, Adrian Morejon and Yuki Matsui each pitched Wednesday and Thursday. Meanwhile, Petco carries a three-year Statcast park factor of 94 for runs, roughly six percent below an average venue.
Arizona Diamondbacks vs. San Diego Padres Odds
| Run Line | Moneyline | Total | |
|---|---|---|---|
| Diamondbacks | +1.5 (-195) | +107 | O 7.5 (-115) |
| Padres | -1.5 (+165) | -128 | U 7.5 (-105) |
Odds accurate as of September 25, 2026 via TheSpread.com. Odds change, get the latest MLB Odds – Futures – Props
Arizona Diamondbacks vs. San Diego Padres — Who Is the Public Betting?
| Diamondbacks | 58% | 42% | Padres |
See the latest MLB Public Betting Splits and make smarter wagers!
Diamondbacks vs. Padres Prediction — Which Mize Shows Up, the 2.70 Tiger or the 6.64 Padre?
The gap between these starters is the biggest input on the board. Pfaadt rarely issues free passes, walking just 2.10 batters per nine innings. He also has not allowed an earned run in two starts against San Diego this season. Mize, in contrast, has walked 10 and allowed 16 earned runs over his last five outings. That profile invites traffic, rising pitch counts and a short night. It also matches the one time Arizona has faced him in a Padres uniform.
The market has nudged toward Arizona as well. The moneyline opened at Padres -133 and D-backs +111 before moving to -128 and +107. However, 58% of run-line bets are on Arizona, so that drift runs with the public and offers only mild support. The run line, meanwhile, has moved slightly toward San Diego.
The case for San Diego is real. The Padres have won eight of 10, and Jake Cronenworth is 11-for-27 lifetime against Pfaadt. Their bullpen has also been the better unit this season. That is why this read targets the stretch the starters control, before relief depth can swing a close game.
The Pick: Diamondbacks First 5 Innings Moneyline (+105)
Diamondbacks vs. Padres Prediction — Padres Relievers Logged 14 Innings in Three Games at Dodger Stadium
Petco Park explains why this total is modest. Still, several inputs lean toward runs. Mize has allowed 2.21 home runs per nine innings since the trade, and his recent starts have ended early. That hands the middle innings to a bullpen whose top arms worked on back-to-back nights. Both offenses are also warm. San Diego has scored 60 runs over its last 10 games. Arizona has 37 during its five-game win streak, though 24 came in three games at Coors Field. The market leans the same way, as the over price has shortened since the open while the number has held.
On the other side, Pfaadt limits walks and has worked at least six innings in eight of his last 10 starts. The four meetings at Petco this season produced 8, 5, 14 and 4 total runs, so this park can cap scoring quickly. This play also leans on the same Mize read as the first pick, so the two are not independent.
The Pick: Over 7.5 (-115)
Final Thoughts and Bonus Angle
Arizona needs this game far more than San Diego does, but urgency alone is not an edge. The case rests on the pitching gap and a tired Padres bullpen. Nothing else on the board justifies a third play. For the other half of the wild-card chase, see our Rays vs. Phillies prediction.
Recap: our picks are the Diamondbacks First 5 Innings Moneyline (+105) and Over 7.5 (-115).
MLB Diamondbacks vs. Padres FAQ: September 25, 2026
What time does the Diamondbacks vs. Padres game start?
The Diamondbacks and Padres start at 9:40 PM ET on Friday, September 25, which is 6:40 PM local time in San Diego. The game at Petco Park opens a three-game series that closes the regular season for both clubs, with Arizona still chasing a wild-card spot.
What channel is the Diamondbacks vs. Padres game on?
Friday’s Diamondbacks vs. Padres game airs on the clubs’ own networks. Padres.TV carries the San Diego broadcast, while DBACKS.TV carries the Arizona broadcast for D-backs fans. Coverage from Petco Park begins with first pitch at 9:40 PM ET, which is 6:40 PM local time.
Who is pitching for the Padres tonight?
Right-hander Casey Mize starts for San Diego. He is 6-9 with a 3.96 ERA across 25 starts this season, split between Detroit and San Diego. Since joining the Padres, he has a 6.64 ERA in nine starts. Arizona counters with right-hander Brandon Pfaadt, who is 7-3 with a 3.72 ERA.
Where do the Diamondbacks and Padres stand in the NL West?
San Diego is 89-70, second in the NL West, and holds the top NL wild-card spot after clinching a postseason berth. Arizona is 85-74, third in the division and two games behind Philadelphia for the final wild-card berth. The D-backs enter Friday with an elimination number of two and three games left.
What is the season series record between the Diamondbacks and Padres?
The season series between the Diamondbacks and Padres is tied 5-5 entering this weekend. San Diego won the most recent meeting 5-1 at Chase Field on Aug. 6. The clubs also split four games at Petco Park in July and split two games in Mexico City in April.