The first-place Milwaukee Brewers head into today's rubber match against the Seattle Mariners as a -127 home moneyline favorite, with first pitch at American Family Field scheduled for 2:10 p.m. ET.
With Robert Gasser in good form at home and George Kirby getting hit around lately, my Mariners vs. Brewers predictions are targeting Milwaukee to take the finale.
Find out more in my MLB picks for Thursday, Aug. 20.
Who will win Mariners vs Brewers today: Brewers moneyline (-131)
The Milwaukee Brewers hand Robert Gasser the baseball, and he's posted a 3.40 FIP across his last four appearances. Gasser has been sharp at American Family Field, owning a 3.80 FIP, compared to a 5.38 mark on the road.
The Seattle Mariners are also slightly worse offensively away from home with a 95 wRC+, 10 points below their home mark.
George Kirby is a wild card right now, allowing 1.86 HR/9 across his previous two starts, with a concerning 6.50 FIP. Milwaukee’s numbers are slightly inflated by a 22-run explosion, but the Brewers still own a 117 wRC+ over the last week.
Milwaukee can jump on Kirby, while Gasser keeps them in it.
Play to -140.
COVERS INTEL: Kirby is having real trouble with the long ball right now. He's allowed 2.61 HR/9 over the last month, compared to his season average of just 1.12. 
Mariners vs Brewers Over/Under pick: Over 8.5 (+109)
This total sits at 8.5, and I'm liking the Over. Both offenses are swinging it well, with Seattle posting a 118 wRC+ over its last six games and Milwaukee sitting at 117 during that same span.
The Brewers’ bullpen has been excellent lately with a 2.24 xERA and minimal homer damage, which keeps this from being a sure thing. However, Kirby’s recent home run issues give Milwaukee a clear scoring path.
Seattle’s relief corps is also a major concern, posting a 5.35 FIP over its last 20 1/3 innings while allowing 2.21 HR/9.
Play to +100.
Mariners vs Brewers home run prediction: William Contreras (+475)
William Contreras has just one home run over his last six contests, but the underlying numbers point to another bomb today. The Brewers catcher owns a 65% hard-hit rate and 20% barrel rate over his last 25 plate appearances.
He also has a .550 xSLG during that span, with 45% of his contact coming in the air. Kirby has a 48.6% fly-ball rate over his last two appearances, and his homer problems are evident. The Mariners’ pen is also long-ball prone.
Whether it comes against Kirby or a reliever, Contreras has multiple paths to a home run.
Play to +600.
- ML/RL bets: 55-64, -16.87 units
- Over/Under bets: 66-50, +6.85 units
Mariners vs Brewers weather
Weather at American Family Field looks excellent today, with clear skies, temperatures around 77°F, light winds near 6 mph, and a 0% chance of rain. Because Milwaukee has a retractable roof, conditions may be neutralized if it is closed, but if open, weather still looks clean with no delay concern.
Mariners vs Brewers odds
- Moneyline: Mariners +119 | Brewers -131
- Run line: Mariners +1.5 (-183) | Brewers -1.5 (+158)
- Over/Under: Over 8.5 (+109) | Under 8.5 (-121)
Mariners vs Brewers trend
The Brewers have hit the moneyline in 34 of their last 50 games at home (+9.25 Units / 11% ROI). Find more MLB betting trends for Mariners vs. Brewers.
How to watch Mariners vs Brewers and game info
| Location | American Family Field, Milwaukee, WI |
| Date | Thursday, Aug. 20, 2026 |
| First pitch | 2:10 p.m. ET |
| TV | Brewers.TV, Mariners.TV |
| Mariners starting pitcher | George Kirby (8-9, 3.89 ERA) |
| Brewers starting pitcher | Robert Gasser (3-5, 4.54 ERA) |
Mariners vs Brewers latest injuries
Odds are correct at the time of publishing and are subject to change.
Not intended for use in MA.
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