MLB matchup analysis
Mariners vs Athletics Prediction, Odds and Model Pick
Friday, September 11, 2026 at Sutter Health Park · 9:40 PM ET
Leo decision: Pass on Mariners vs Athletics
The case for Seattle Mariners
The case for Athletics
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
Mariners 5, Athletics 6
How the analysis held up
Athletics won. Leo's model favored the other side.
Leo's two internal reads disagreed pregame by 62.3 points — the team-strength model favored Seattle Mariners, the run-projection model favored Athletics. The run-projection model had the winner here.
George Kirby (Seattle Mariners) was Leo's favored starter by pitcher score, but Jeffrey Springs actually pitched better tonight: 5.0 IP, 2 ER (3.60 ERA) against 6.0 IP, 4 ER (6.00 ERA). The edge did not show up in this game.
The Athletics bullpen was not flagged pregame, but it had a night worth noting: 1 earned run allowed over 5.0 relief innings (1.80 ERA) — quietly better than the pregame read implied. Note: 2 of the runs charged to the Athletics pitching staff overall were unearned — not something the bullpen's stuff should be blamed for.
Seattle Mariners scored 5 in a game that went 10 innings — not compared against the 3.9 pregame projection, which assumed nine.
Athletics scored 6 in a game that went 10 innings — not compared against the 5.4 pregame projection, which assumed nine.
Likely driver: George Kirby, the pick's own starter, was rocked for a 6.00 ERA, and the Athletics bullpen quietly shut the game down (1.80 ERA over 5.0 innings), unflagged pregame.
Game information
| Matchup | Seattle Mariners at Athletics |
|---|---|
| Date | Friday, September 11, 2026 |
| First pitch | 9:40 PM ET |
| Venue | Sutter Health Park |
| Starting pitchers | George Kirby vs Jeffrey Springs |
| Weather | Game-time forecast: 82°F, 0% precipitation chance, 6 mph wind from S. |
Starting pitcher matchup
Full Pitcher Matchup Tool →| Metric | Mariners | Athletics |
|---|---|---|
| Pitching plan | Traditional starter | Traditional starter |
| Expected innings | 6 | 5 |
| Throws | R | L |
| Leo pitcher score (higher is better) | 62 | 46 |
| ERA (lower is better) | 4.18 | 6.02 |
| WHIP (lower is better) | 1.34 | 1.45 |
| K/9 (higher is better) | 7.5 | 7.2 |
| K-BB% (higher is better) | 14.4% | 9.1% |
| K% (higher is better) | 19.9% | 18.2% |
| BB% (lower is better) | 5.5% | 9.1% |
| BB/9 (lower is better) | 2.1 | 3.6 |
| HR/9 (lower is better) | 1.1 | 2.3 |
| Ground-ball rate | 47.3% | 40.8% |
| Fly-ball rate | 52.7% | 59.2% |
Pitcher edge: Leo gives George Kirby a 16-point edge over Jeffrey Springs, driven mainly by HR/9 (1.13 vs 2.28) and BB/9 (2.1 vs 3.6).
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 →Mariners are 5-5 in their last 10 and averaging 4.2 runs per game over the last 15 days; Athletics are 6-4 in their last 10 and averaging 4.3 runs per game over the last 15 days. On the season Mariners carry the better run differential per game (-0.51 against -1.26).
| Metric | Mariners | Athletics |
|---|---|---|
| Last 10 | 5-5 | 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 | 0.667 | 0.721 |
| wOBA, last 15 days (hot/cold read) | 0.299 | 0.319 |
| Runs per game, last 15 days | 4.2 | 4.3 |
| K% last 15 days (lower is better) | 24.9% | 21.5% |
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 | Mariners | Athletics |
|---|---|---|
| OPS | 0.693 (+0.010 vs szn) | 0.754 (+0.031 vs szn) |
| Runs per game | 4.39 (+0.433 vs szn) | 4.54 (+0.164 vs szn) |
| wOBA (model offense input) | 0.309 | 0.333 (+0.014 vs szn) |
| K% (lower is better) | 25.0% (+1.7% vs szn) | 21.0% (-1.5% vs szn) |
Over the last 30 days the Athletics have been the better offense, 0.333 wOBA to 0.309. They are running hot against their own season line (+0.014 wOBA). Mariners are striking out at 25.0% over the window — something the opposing starter can lean on.
Season profile
Full Stats page →| Metric | Mariners | Athletics |
|---|---|---|
| Record | 69-78 | 59-88 |
| Run differential / game (team quality) | -0.51 | -1.26 |
| Runs scored / game (offense, season) | 3.96 | 4.37 |
| Runs allowed / game (defense, season, lower better) | 4.47 | 5.63 |
| Season OPS | 0.682 | 0.721 |
| K% season (lower is better) | 23.3% | 22.5% |
| OPS vs opposing hand (season) | 0.627 | 0.719 |
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.
The Map
Full interactive map →Every team on today's slate, on any two axes you pick. Mariners and Athletics 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 | Mariners | Athletics |
|---|---|---|
| Fatigue | 6.2/10, Tired | 6.1/10, Normal |
| Efficiency | 5.0/10, Average | 6.9/10, Effective |
| Combined risk | 6.2/10, Tired | 5.2/10, Normal |
| Relief innings, last 7 days | 18.0 | 24.3 |
| Back-to-back arms | 4 | 5 |
| 7-day ERA | 4.50 | 1.48 |
| 7-day WHIP | 1.17 | 1.15 |
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 and market are close. Team totals remain research-only until their graded sample is established.
More games today
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