MLB matchup analysis
Rangers vs Diamondbacks Prediction, Odds and Model Pick
Saturday, September 12, 2026 at Chase Field · 8:10 PM ET
Leo decision: Pass on Rangers vs Diamondbacks
The case for Arizona Diamondbacks
The case for Texas Rangers
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
Rangers 6, Diamondbacks 2
How the analysis held up
Texas Rangers won. Leo's model favored the other side.
Brandon Pfaadt (Arizona Diamondbacks) was Leo's favored starter by pitcher score, but Kumar Rocker actually pitched better tonight: 4.0 IP, 1 ER (2.25 ERA) against 6.2 IP, 6 ER (8.10 ERA). The edge did not show up in this game.
The Texas Rangers bullpen was flagged as elevated risk pregame (Tired). In relief it actually allowed 1 earned run over 5.0 innings (1.80 ERA) — the risk read did not show up on the scoreboard tonight.
The Arizona Diamondbacks bullpen was flagged as elevated risk pregame (Tired). In relief it actually allowed 0 earned runs over 2.1 innings (0.00 ERA) — the risk read did not show up on the scoreboard tonight.
Texas Rangers scored 6, 3.4 more than the 2.6 pregame projection.
Arizona Diamondbacks scored 2, 2.4 fewer than the 4.4 pregame projection.
Likely driver: Brandon Pfaadt, the pick's own starter, was rocked for a 8.10 ERA, and Texas Rangers's offense scored 3.4 more runs than projected.
Game information
| Matchup | Texas Rangers at Arizona Diamondbacks |
|---|---|
| Date | Saturday, September 12, 2026 |
| First pitch | 8:10 PM ET |
| Venue | Chase Field |
| Starting pitchers | Kumar Rocker vs Brandon Pfaadt |
| Weather | Game-time forecast: 96°F, 1% precipitation chance, 14 mph wind from SW. This venue has a roof, but the roof status is not confirmed. |
Starting pitcher matchup
Full Pitcher Matchup Tool →| Metric | Rangers | Diamondbacks |
|---|---|---|
| Pitching plan | Traditional starter | Traditional starter |
| Expected innings | 4⅔ | 5⅔ |
| Throws | R | R |
| Leo pitcher score (higher is better) | 57 | 70 |
| ERA (lower is better) | 4.59 | 3.50 |
| WHIP (lower is better) | 1.43 | 1.15 |
| K/9 (higher is better) | 8.4 | 5.9 |
| K-BB% (higher is better) | 12.1% | 9.9% |
| K% (higher is better) | 21.3% | 15.8% |
| BB% (lower is better) | 9.2% | 6.0% |
| BB/9 (lower is better) | 3.7 | 2.2 |
| HR/9 (lower is better) | 1.3 | 1.0 |
| Ground-ball rate | 45.9% | 48.5% |
| Fly-ball rate | 54.1% | 51.5% |
Pitcher edge: Leo gives Brandon Pfaadt a 13-point edge over Kumar Rocker, driven mainly by BB/9 (2.2 vs 3.7) and expected innings (5.7 vs 4.7).
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 →Rangers are 4-6 in their last 10 and averaging 4.9 runs per game over the last 15 days; Diamondbacks are 6-4 in their last 10 and averaging 3.9 runs per game over the last 15 days. Season run differential separates them by almost nothing (-0.30 against +0.02).
| Metric | Rangers | Diamondbacks |
|---|---|---|
| Last 10 | 4-6 | 6-4 |
| Last 10 by venue (away team on the road, home team at home) | 3-7 on the road | 5-5 at home |
| OPS, last 15 days | 0.736 | 0.673 |
| wOBA, last 15 days (hot/cold read) | 0.324 | 0.298 |
| Runs per game, last 15 days | 4.9 | 3.9 |
| K% last 15 days (lower is better) | 23.1% | 21.4% |
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 | Rangers | Diamondbacks |
|---|---|---|
| OPS | 0.734 (+0.016 vs szn) | 0.693 (-0.016 vs szn) |
| Runs per game | 4.29 (+0.145 vs szn) | 3.96 (-0.460 vs szn) |
| wOBA (model offense input) | 0.323 | 0.306 (-0.007 vs szn) |
| K% (lower is better) | 22.6% | 20.2% (+0.8% vs szn) |
Over the last 30 days the Rangers have been the better offense, 0.323 wOBA to 0.306.
Season profile
Full Stats page →| Metric | Rangers | Diamondbacks |
|---|---|---|
| Record | 72-76 | 79-69 |
| Run differential / game (team quality) | -0.30 | +0.02 |
| Runs scored / game (offense, season) | 4.14 | 4.42 |
| Runs allowed / game (defense, season, lower better) | 4.44 | 4.40 |
| Season OPS | 0.716 | 0.710 |
| K% season (lower is better) | 22.8% | 19.3% |
| OPS vs opposing hand (season) | 0.695 | 0.684 |
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. Rangers and Diamondbacks 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 | Rangers | Diamondbacks |
|---|---|---|
| Fatigue | 7.2/10, Tired | 8.1/10, Tired |
| Efficiency | 4.1/10, Below average | 6.5/10, Effective |
| Combined risk | 7.7/10, Tired | 7.4/10, Tired |
| Relief innings, last 7 days | 23.0 | 34.0 |
| Back-to-back arms | 6 | 8 |
| 7-day ERA | 5.48 | 2.38 |
| 7-day WHIP | 1.39 | 1.06 |
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 current model and market total cannot be compared yet. Team totals remain research-only until their graded sample is established.
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