MLB matchup analysis

Diamondbacks vs Padres Prediction, Odds and Model Pick

Friday, September 25, 2026 at Petco Park · 9:40 PM ET

Pass

Leo decision: Pass on Diamondbacks vs Padres

Lab Rating
5.0/10
Model lean
Padres 52.6%
Market probability
52.9%
Model edge
-0.3%
Best moneyline
-118
Sportsbooks checked
3
Leo model
52.6%
Market
52.9%

The case for San Diego Padres

Bats are hot: +0.047 wOBA
San Diego Padres is outhitting its own season form over the last 15 days. Recent form is context, not a model input, but it points the same way here.

The case for Arizona Diamondbacks

Late-inning bullpen advantage
San Diego Padres relievers have a 1.98 ERA over the last 7 days; Arizona Diamondbacks relievers have a 3.86. San Diego Padres also have 7 arms pitching on back-to-back days, against 4 for Arizona Diamondbacks. If this is still close after six innings, that gap favors Arizona Diamondbacks.
Their bats are hot: +0.048 wOBA
Arizona Diamondbacks is outhitting its own season form over the last 15 days.

Why it is not official

Below the 61.0% official gate
Win probability is 52.6%. Leo does not make a game official below 61.0%, no matter how good the price is. This is a value spot, not a high-confidence winner.
Setup quality below the bar
Lab Rating is 5.0/10, under the 7.2/10 required for an official pick.
Own bullpen carries risk: 8.6/10
The San Diego Padres bullpen comes in high risk. A lead after six innings is less safe than usual.

Why the setup score is what it is

Conviction: 0/10
Leo's own win probability for San Diego Padres (52.6%) is close enough to a coin flip that the rating credits little or no conviction -- credit only starts above 55%.
Pitching plan: 22.67/40
Casey Mize rates 67 on Leo's pitcher score, judged on its own merits (50-80 is the credited range). That is a strong start on its own, and it earns most or all of the available credit here.
Offense: 27.67/50
San Diego Padres's recent offensive form clearly outpaces Arizona Diamondbacks's over the tracked windows.

Why the price is what it is

Team strength: 60.9%
Before any pitcher or bullpen adjustment, Leo's team-strength model alone makes San Diego Padres 60.9% to win. Everything below moves the price from this starting point.
Pitcher score gap: 1 points
The pitcher-score gap favors Arizona Diamondbacks by 1 points. This is the biggest single mover of the price -- a large gap moves it a lot, a small gap barely moves it.
Bullpen adjustment: -0.081
The bullpen-fatigue gap between the two pens nudges the price toward Arizona Diamondbacks. This moves the price less than the starting pitchers do, since a starter covers more of the game than the bullpen.
Net effect: 60.9% -> 52.6%
Team strength alone had San Diego Padres at 60.9%. After the pitcher and bullpen terms, the price is 52.6% -- the same number shown as Model Lean above.
The verdict Leo passes. The combined Lab Rating did not clear the official threshold.
Read the full model output

The combined Lab Rating did not clear the official threshold.

Final result

Diamondbacks 11, Padres 4

How the analysis held up

Arizona Diamondbacks won. Leo's model favored the other side.

Brandon Pfaadt (No clear pitching-plan edge), the starter Leo's pitcher score favored, actually outpitched Casey Mize: 7.2 IP, 4 ER (4.70 ERA) against 4.0 IP, 7 ER (15.75 ERA). The edge held up.

The Arizona Diamondbacks bullpen was not flagged pregame, but it had a night worth noting: 0 earned runs allowed over 1.1 relief innings (0.00 ERA) — quietly better than the pregame read implied.

The San Diego Padres bullpen was flagged as elevated risk pregame (High risk). In relief it actually allowed 4 earned runs over 5.0 innings (7.20 ERA) — the risk read showed up.

Arizona Diamondbacks scored 11, 7.3 more than the 3.7 pregame projection.

San Diego Padres scored 4, 1.8 fewer than the 5.8 pregame projection.

Likely driver: Casey Mize, the pick's own starter, was rocked for a 15.75 ERA, and Arizona Diamondbacks's offense scored 7.3 more runs than projected.

Game information

MatchupArizona Diamondbacks at San Diego Padres
DateFriday, September 25, 2026
First pitch9:40 PM ET
VenuePetco Park
Starting pitchersBrandon Pfaadt vs Casey Mize
WeatherGame-time forecast: 73°F, 0% precipitation chance, 5 mph wind from NW.

Starting pitcher matchup

Full Pitcher Matchup Tool →
Brandon PfaadtDiamondbacks · RHP
vs
Casey MizePadres · RHP
MetricDiamondbacksPadres
Pitching planTraditional starterTraditional starter
Expected innings65
ThrowsRR
Leo pitcher score (higher is better)6867
ERA (lower is better)3.723.96
WHIP (lower is better)1.171.19
K/9 (higher is better)6.17.7
K-BB% (higher is better)10.7%13.8%
K% (higher is better)16.4%20.6%
BB% (lower is better)5.6%6.8%
BB/9 (lower is better)2.12.5
HR/9 (lower is better)1.01.1
Ground-ball rate48.6%36.6%
Fly-ball rate51.4%63.4%

Pitcher edge: Leo gives Brandon Pfaadt a 1-point edge over Casey Mize, driven mainly by expected innings (5.9 vs 5.1) and BB/9 (2.1 vs 2.5).

How to read this: the scorecards above name the starters; every number lives in this table.

Strikeout Projections Full strikeout projections →

Brandon Pfaadt strikeouts
3.6 Leo projected Ks
No K play · +0.1K difference is below Leo's 0.7K threshold
Market 3.5K · O -132 / U +107 · 6 books
Casey Mize strikeouts
3.3 Leo projected Ks
No strikeout line posted when this page was generated

Same data source as the Pitcher Matchup Tool, where every starter on the slate is compared side by side.

Diamondbacks are 6-4 in their last 10 and averaging 5.8 runs per game over the last 15 days; Padres are 8-2 in their last 10 and averaging 6.2 runs per game over the last 15 days. Season run differential separates them by almost nothing (+0.11 against +0.21).

MetricDiamondbacksPadres
Last 106-48-2
Last 10 by venue (away team on the road, home team at home)8-2 on the road8-2 at home
OPS, last 15 days0.8450.839
wOBA, last 15 days (hot/cold read)0.3640.363
Runs per game, last 15 days5.86.2
K% last 15 days (lower is better)19.9%21.0%

Last 15 days only. Hot and cold streaks for all 30 teams live on the Stats page.

30-day offense

Full offense tool →
Last 30 daysDiamondbacksPadres
OPS0.747 (+0.026 vs szn)0.766 (+0.051 vs szn)
Runs per game4.63 (+0.080 vs szn)5.07 (+0.680 vs szn)
wOBA (model offense input)0.326 (+0.009 vs szn)0.334 (+0.019 vs szn)
K% (lower is better)20.8% (+1.4% vs szn)20.8% (-0.8% vs szn)

Over the last 30 days the Padres have been the better offense, 0.334 wOBA to 0.326. They are running hot against their own season line (+0.019 wOBA).

Season profile

Full Stats page →
MetricDiamondbacksPadres
Record85-7489-70
Run differential / game (team quality)+0.11+0.21
Runs scored / game (offense, season)4.554.39
Runs allowed / game (defense, season, lower better)4.444.19
Season OPS0.7190.715
K% season (lower is better)19.4%21.6%
OPS vs opposing hand (season)0.6940.719

Season-long team quality, not recent form. Run differential and run environment come from the season standings; splits for all 30 teams live on the Stats page, including the run environment table.

Every team on today's slate, on any two axes you pick. Diamondbacks and Padres are highlighted.

Diamondbacks
Combined risk
5.9 Normal
Fatigue
6.1 Normal
Efficiency
5.5 Effective
Padres
Combined risk
8.6 High risk
Fatigue
9.3 High risk
Efficiency
6.5 Effective

Risk is what the model actually uses: fatigue blended with how well the pen has pitched. High fatigue with high efficiency is a tired pen that is still getting outs.

MetricDiamondbacksPadres
Fatigue6.1/10, Normal9.3/10, High risk
Efficiency5.5/10, Effective6.5/10, Effective
Combined risk5.9/10, Normal8.6/10, High risk
Relief innings, last 7 days23.327.3
Back-to-back arms47
7-day ERA3.861.98
7-day WHIP1.111.21

Fatigue measures workload. Efficiency measures recent run prevention. Combined risk is what the moneyline and totals systems use.

Run total projection

Full Totals Projections →
Leo projection
9.5
Market total
7.5
Projected away runs
3.7
Projected home runs
5.8
Over price
-113
Under price
-102
Arizona Diamondbacks team total
3.7 projected
Line 3.5 · O -107 / U -115
No team-total lean
San Diego Padres team total
5.8 projected
Line 3.5 · O -127 / U +105
Over research lean (+2.3)

The model projects 2.0 runs above the market total. A research lean still requires a setup rating of at least 7.0/10. Team totals remain research-only until their graded sample is established.

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Model outputs are not guarantees. Leo provides analysis and education only. Every official pick remains visible on the Results page. 21+. If you or someone you know has a gambling problem, call 1-800-GAMBLER.