MLB matchup analysis
Phillies vs Diamondbacks Prediction, Odds and Model Pick
Monday, August 31, 2026 at Chase Field · 9:40 PM ET
LyDia decision: Pass on Phillies vs Diamondbacks
The case for Arizona Diamondbacks
The case for Philadelphia Phillies
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
Phillies 2, Diamondbacks 1
How the analysis held up
Philadelphia Phillies won. LyDia's model favored the other side.
LyDia's two internal reads disagreed pregame by 60.6 points — the team-strength model favored Arizona Diamondbacks, the run-projection model favored Philadelphia Phillies. The run-projection model had the winner here.
Brandon Pfaadt (Arizona Diamondbacks) was LyDia's favored starter by pitcher score, but Aaron Nola actually pitched better tonight: 5.0 IP, 1 ER (1.80 ERA) against 6.0 IP, 2 ER (3.00 ERA). The edge did not show up in this game.
The Philadelphia Phillies bullpen was not flagged pregame, but it had a night worth noting: 0 earned runs allowed over 4.0 relief innings (0.00 ERA) — quietly better than the pregame read implied.
The Arizona Diamondbacks bullpen was flagged as elevated risk pregame (Tired). In relief it actually allowed 0 earned runs over 3.0 innings (0.00 ERA) — the risk read did not show up on the scoreboard tonight.
Philadelphia Phillies scored 2, 4.7 fewer than the 6.7 pregame projection.
Arizona Diamondbacks scored 1, 3.8 fewer than the 4.8 pregame projection.
Likely driver: the Philadelphia Phillies bullpen quietly shut the game down (0.00 ERA over 4.0 innings), unflagged pregame, and Arizona Diamondbacks's offense scored 3.8 fewer runs than projected.
Game information
| Matchup | Philadelphia Phillies at Arizona Diamondbacks |
|---|---|
| Date | Monday, August 31, 2026 |
| First pitch | 9:40 PM ET |
| Venue | Chase Field |
| Starting pitchers | Aaron Nola vs Brandon Pfaadt |
| Weather | Game-time forecast: 86°F, 0% precipitation chance, 2 mph wind from SW. This venue has a roof, but the roof status is not confirmed. |
Starting pitcher matchup
Full Pitcher Matchup Tool →| Metric | Phillies | Diamondbacks |
|---|---|---|
| Pitching plan | Traditional starter | Traditional starter |
| Expected innings | 5⅓ | 6 |
| Throws | R | R |
| LyDia pitcher score (higher is better) | 56 | 70 |
| ERA (lower is better) | 5.03 | 3.51 |
| WHIP (lower is better) | 1.40 | 1.14 |
| K/9 (higher is better) | 9.6 | 6.2 |
| K-BB% (higher is better) | 16.9% | 10.7% |
| K% (higher is better) | 24.8% | 16.7% |
| BB% (lower is better) | 8.0% | 6.0% |
| BB/9 (lower is better) | 3.1 | 2.2 |
| HR/9 (lower is better) | 2.0 | 1.0 |
| Ground-ball rate | 46.2% | 49.1% |
| Fly-ball rate | 53.8% | 50.9% |
Pitcher edge: LyDia gives Brandon Pfaadt a 14-point edge over Aaron Nola, driven mainly by HR/9 (1.03 vs 2.01) and ERA (3.51 vs 5.03).
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 →Phillies are 8-2 in their last 10 and averaging 5.5 runs per game over the last 15 days; Diamondbacks are 6-4 in their last 10 and averaging 4.4 runs per game over the last 15 days. Season run differential separates them by almost nothing (+0.22 against +0.03).
| Metric | Phillies | Diamondbacks |
|---|---|---|
| Last 10 | 8-2 | 6-4 |
| Last 10 by venue (away team on the road, home team at home) | 8-2 on the road | 5-5 at home |
| OPS, last 15 days | 0.762 | 0.694 |
| wOBA, last 15 days (hot/cold read) | 0.335 | 0.307 |
| Runs per game, last 15 days | 5.5 | 4.4 |
| K% last 15 days (lower is better) | 15.8% | 19.0% |
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 days | Phillies | Diamondbacks |
|---|---|---|
| OPS | 0.763 (+0.048 vs szn) | 0.748 (+0.035 vs szn) |
| Runs per game | 5.25 (+0.728 vs szn) | 4.48 (-0.021 vs szn) |
| wOBA (model offense input) | 0.336 (+0.021 vs szn) | 0.329 (+0.014 vs szn) |
| K% (lower is better) | 15.9% (-6.2% vs szn) | 19.2% |
Over the last 30 days the Phillies have been the better offense, 0.336 wOBA to 0.329. They are running hot against their own season line (+0.021 wOBA).
Season profile
Full Stats page →| Metric | Phillies | Diamondbacks |
|---|---|---|
| Record | 77-60 | 73-65 |
| Run differential / game (team quality) | +0.22 | +0.03 |
| Runs scored / game (offense, season) | 4.52 | 4.50 |
| Runs allowed / game (defense, season, lower better) | 4.30 | 4.47 |
| Season OPS | 0.716 | 0.714 |
| K% season (lower is better) | 22.1% | 19.2% |
| OPS vs opposing hand (season) | 0.721 | 0.687 |
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. Phillies 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 | Phillies | Diamondbacks |
|---|---|---|
| Fatigue | 5.0/10, Normal | 7.3/10, Tired |
| Efficiency | 6.4/10, Effective | 4.7/10, Average |
| Combined risk | 4.3/10, Normal | 7.5/10, Tired |
| Relief innings, last 7 days | 17.0 | 22.0 |
| Back-to-back arms | 5 | 6 |
| 7-day ERA | 2.65 | 4.50 |
| 7-day WHIP | 1.00 | 1.36 |
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 4.4 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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