MLB matchup analysis

Mariners vs Rockies Prediction, Odds and Model Pick

Saturday, September 19, 2026 at Coors Field · 8:10 PM ET

Pass

Leo decision: Pass on Mariners vs Rockies

Lab Rating
5.5/10
Model lean
Mariners 74.0%
Market probability
57.5%
Model edge
+16.4%
Best moneyline
-143
Sportsbooks checked
9
Leo model
74.0%
Market
57.5%

The case for Seattle Mariners

Starting pitcher edge: 23 points
Leo gives Bryce Miller a 23-point edge over Jose Quintana, driven mainly by K-BB% (16.5% vs 1.7%) and K/9 (8.9 vs 4.4).
Late-inning bullpen advantage
Colorado Rockies relievers have a 6.00 ERA over the last 7 days; Seattle Mariners relievers have a 3.60. Colorado Rockies also have 5 arms pitching on back-to-back days, against 2 for Seattle Mariners. If this is still close after six innings, that gap favors Seattle Mariners.
Bats are hot: +0.029 wOBA
Seattle Mariners 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 Colorado Rockies

Their bats are hot: +0.014 wOBA
Colorado Rockies is outhitting its own season form over the last 15 days.

Why it is not official

Setup quality below the bar
Lab Rating is 5.5/10, under the 7.2/10 required for an official pick.
Opponent is swinging it
The other lineup is +0.014 wOBA above its season form over the last 15 days.

Why the setup score is what it is

Conviction: 9.48/10
Leo's win probability for Seattle Mariners (74.0%) is well clear of a coin flip -- this is a real, stated lean, not a guess.
Pitching plan: 22.67/40
Bryce Miller 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: 22.81/50
Seattle Mariners's recent form does not clearly outpace Colorado Rockies's.

Why the price is what it is

Team strength: 46.0%
Before any pitcher or bullpen adjustment, Leo's team-strength model alone makes Seattle Mariners 46.0% to win. Everything below moves the price from this starting point.
Pitcher score gap: 23 points
The pitcher-score gap favors Seattle Mariners by 23 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: +0.15
The bullpen-fatigue gap between the two pens nudges the price toward Seattle Mariners. This moves the price less than the starting pitchers do, since a starter covers more of the game than the bullpen.
Net effect: 46.0% -> 74.0%
Team strength alone had Seattle Mariners at 46.0%. After the pitcher and bullpen terms, the price is 74.0% -- 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.

Game information

MatchupSeattle Mariners at Colorado Rockies
DateSaturday, September 19, 2026
First pitch8:10 PM ET
VenueCoors Field
Starting pitchersBryce Miller vs Jose Quintana
WeatherGame-time forecast: 74°F, 59% precipitation chance, 5 mph wind from S.

Starting pitcher matchup

Full Pitcher Matchup Tool →
Bryce MillerMariners · RHP
vs
Jose QuintanaRockies · LHP
MetricMarinersRockies
Pitching planTraditional starterTraditional starter
Expected innings5⅓4⅔
ThrowsRL
Leo pitcher score (higher is better)6744
ERA (lower is better)4.195.27
WHIP (lower is better)1.161.51
K/9 (higher is better)8.94.4
K-BB% (higher is better)16.5%1.7%
K% (higher is better)24.3%11.0%
BB% (lower is better)7.8%9.4%
BB/9 (lower is better)2.93.7
HR/9 (lower is better)1.71.3
Ground-ball rate42.4%41.8%
Fly-ball rate57.6%58.2%

Pitcher edge: Leo gives Bryce Miller a 23-point edge over Jose Quintana, driven mainly by K-BB% (16.5% vs 1.7%) and K/9 (8.9 vs 4.4).

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

Strikeout Projections Full strikeout projections →

Bryce Miller strikeouts
5.5 Leo projected Ks
Qualifying projection: OVER 4.5K · +1.0K difference
Market 4.5K · O +116 / U -135 · 5 books
Jose Quintana strikeouts
2.3 Leo projected Ks
No K play · -0.2K difference is below Leo's 0.7K threshold
Market 2.5K · O +140 / U -150 · 3 books

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

Mariners are 5-5 in their last 10 and averaging 5.4 runs per game over the last 15 days; Rockies are 1-9 in their last 10 and averaging 4.7 runs per game over the last 15 days. On the season Mariners carry the better run differential per game (-0.36 against -1.16).

MetricMarinersRockies
Last 105-51-9
Last 10 by venue (away team on the road, home team at home)5-5 on the road4-6 at home
OPS, last 15 days0.7730.775
wOBA, last 15 days (hot/cold read)0.3370.340
Runs per game, last 15 days5.44.7
K% last 15 days (lower is better)20.5%22.1%

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 daysMarinersRockies
OPS0.727 (+0.034 vs szn)0.745
Runs per game4.93 (+0.842 vs szn)4.07 (-0.608 vs szn)
wOBA (model offense input)0.322 (+0.013 vs szn)0.329
K% (lower is better)23.8% (+0.7% vs szn)23.1%

Over the last 30 days the Rockies have been the better offense, 0.329 wOBA to 0.322.

Season profile

Full Stats page →
MetricMarinersRockies
Record72-8256-98
Run differential / game (team quality)-0.36-1.16
Runs scored / game (offense, season)4.084.68
Runs allowed / game (defense, season, lower better)4.445.84
Season OPS0.6930.742
K% season (lower is better)23.1%22.8%
OPS vs opposing hand (season)0.6510.756

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. Mariners and Rockies are highlighted.

Mariners
Combined risk
4.9 Normal
Fatigue
5.1 Normal
Efficiency
5.4 Average
Rockies
Combined risk
10.0 High risk
Fatigue
9.6 High risk
Efficiency
3.5 Below average

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.

MetricMarinersRockies
Fatigue5.1/10, Normal9.6/10, High risk
Efficiency5.4/10, Average3.5/10, Below average
Combined risk4.9/10, Normal10.0/10, High risk
Relief innings, last 7 days20.036.0
Back-to-back arms25
7-day ERA3.606.00
7-day WHIP1.301.56

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
8.4
Market total
11.0
Projected away runs
4.9
Projected home runs
3.1
Over price
+103
Under price
-114
Seattle Mariners team total
4.9 projected
Line 5.5 · O -125 / U +105
No team-total lean
Colorado Rockies team total
3.1 projected
Line 4.5 · O -115 / U +100
Under research lean (-1.4)

The model projects 2.6 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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