MLB matchup analysis
Diamondbacks vs Astros Prediction, Odds and Model Pick
Saturday, September 5, 2026 at Daikin Park · 7:15 PM ET
Leo decision: Pass on Diamondbacks vs Astros
The case for Arizona Diamondbacks
The case for Houston Astros
Why it is not official
Why the setup score is what it is
Why the price is what it is
Read the full model output
The combined Lab Rating did not clear the official threshold.
Final result
Diamondbacks 4, Astros 3
How the analysis held up
Arizona Diamondbacks won, the side Leo's model favored.
Brandon Pfaadt (Arizona Diamondbacks) was Leo's favored starter by pitcher score, but Ethan Pecko actually pitched better tonight: 4.1 IP, 1 ER (2.08 ERA) against 6.1 IP, 3 ER (4.26 ERA). The edge did not show up in this game.
The Arizona Diamondbacks bullpen was not flagged pregame, but it had a night worth noting: 0 earned runs allowed over 3.2 relief innings (0.00 ERA) — quietly better than the pregame read implied.
The Houston Astros bullpen was flagged as elevated risk pregame (Tired). In relief it actually allowed 2 earned runs over 5.2 innings (3.18 ERA) — the risk read did not show up on the scoreboard tonight. Note: 1 of the runs charged to the Houston Astros pitching staff overall was unearned — not something the bullpen's stuff should be blamed for.
Game information
| Matchup | Arizona Diamondbacks at Houston Astros |
|---|---|
| Date | Saturday, September 5, 2026 |
| First pitch | 7:15 PM ET |
| Venue | Daikin Park |
| Starting pitchers | Brandon Pfaadt vs Ethan Pecko |
| Weather | Game-time forecast: 84°F, 23% precipitation chance, 6 mph wind from E. This venue has a roof, but the roof status is not confirmed. |
Starting pitcher matchup
Full Pitcher Matchup Tool →| Metric | Diamondbacks | Astros |
|---|---|---|
| Pitching plan | Traditional starter | Limited starter |
| Expected innings | 5⅔ | 4 |
| Throws | R | R |
| Leo pitcher score (higher is better) | 69 | 45 |
| ERA (lower is better) | 3.55 | 4.96 |
| WHIP (lower is better) | 1.14 | 1.47 |
| K/9 (higher is better) | 5.9 | 6.1 |
| K-BB% (higher is better) | 10.0% | 1.4% |
| K% (higher is better) | 16.0% | 15.3% |
| BB% (lower is better) | 6.0% | 13.9% |
| BB/9 (lower is better) | 2.2 | 5.5 |
| HR/9 (lower is better) | 1.0 | 2.2 |
| Ground-ball rate | 48.1% | 30.6% |
| Fly-ball rate | 51.9% | 69.4% |
Pitcher edge: Leo gives Brandon Pfaadt a 24-point edge over Ethan Pecko, driven mainly by BB/9 (2.2 vs 5.5) and HR/9 (1.03 vs 2.20).
How to read this: the scorecards above name the starters; every number lives in this table.
Strikeout Projections Full strikeout projections →
Same data source as the Pitcher Matchup Tool, where every starter on the slate is compared side by side.
Recent form
Full Stats page →Diamondbacks are 5-5 in their last 10 and averaging 3.6 runs per game over the last 15 days; Astros are 7-3 in their last 10 and averaging 4.2 runs per game over the last 15 days. Season run differential separates them by almost nothing (-0.01 against -0.26).
| Metric | Diamondbacks | Astros |
|---|---|---|
| Last 10 | 5-5 | 7-3 |
| Last 10 by venue (away team on the road, home team at home) | 4-6 on the road | 5-5 at home |
| OPS, last 15 days | 0.655 | 0.688 |
| wOBA, last 15 days (hot/cold read) | 0.291 | 0.300 |
| Runs per game, last 15 days | 3.6 | 4.2 |
| K% last 15 days (lower is better) | 20.1% | 22.7% |
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 days | Diamondbacks | Astros |
|---|---|---|
| OPS | 0.705 | 0.653 (-0.070 vs szn) |
| Runs per game | 3.79 (-0.641 vs szn) | 3.89 (-0.622 vs szn) |
| wOBA (model offense input) | 0.311 | 0.286 (-0.031 vs szn) |
| K% (lower is better) | 20.2% (+0.8% vs szn) | 22.1% |
Over the last 30 days the Diamondbacks have been the better offense, 0.311 wOBA to 0.286.
Season profile
Full Stats page →| Metric | Diamondbacks | Astros |
|---|---|---|
| Record | 74-68 | 73-69 |
| Run differential / game (team quality) | -0.01 | -0.26 |
| Runs scored / game (offense, season) | 4.43 | 4.51 |
| Runs allowed / game (defense, season, lower better) | 4.44 | 4.77 |
| Season OPS | 0.708 | 0.723 |
| K% season (lower is better) | 19.4% | 21.6% |
| OPS vs opposing hand (season) | 0.681 | 0.728 |
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.
The Map
Full interactive map →Every team on today's slate, on any two axes you pick. Diamondbacks and Astros are highlighted.
Bullpen matchup
Full Bullpen Fatigue Index →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.
| Metric | Diamondbacks | Astros |
|---|---|---|
| Fatigue | 6.8/10, Tired | 8.0/10, Tired |
| Efficiency | 6.1/10, Effective | 5.2/10, Average |
| Combined risk | 6.3/10, Tired | 7.9/10, Tired |
| Relief innings, last 7 days | 23.7 | 30.3 |
| Back-to-back arms | 7 | 5 |
| 7-day ERA | 2.66 | 3.56 |
| 7-day WHIP | 1.18 | 1.42 |
Fatigue measures workload. Efficiency measures recent run prevention. Combined risk is what the moneyline and totals systems use.
Run total projection
Full Totals Projections →The model projects 1.9 runs below 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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