Hunter Brown and the Houston Astros are hoping to avoid a series sweep when they meet Bryan Woo and the Seattle Mariners.
Brown and Woo have been lights out, and my Astros vs. Mariners prediction anticipates a low-scoring contest at pitcher-friendly T-Mobile Park.
Read on for my MLB picks for Sunday, July 20.
Astros vs Mariners prediction
My Astros vs Mariners best bet: Under 6.5 (-105 at Caesars)
In a typical series between the Seattle Mariners and Houston Astros, runs come at a premium.
This series has been an aberration; they’ve already scored 20 runs during this series, but today's pitching matchup should fuel a return to normal.
Hunter Brown has been tough to hit on the road, giving up only four earned runs across his last four away starts. He’s striking out 10 batters per nine, and he’s fanned 35 Mariners across 104 career at bats.
Seattle righty Bryan Woo is striking out nearly nine hitters per nine frames. He’s especially filthy against righty-heavy lineups like the Astros and has held this Houston lineup to 10 hits across 35 ABs.
Both clubs' home/away splits are in the bottom third in runs scored. Both starters are stingy with the runs in an extremely pitcher-friendly park.
I’ll avoid most of the bullpen issues because Brown and Woo pitch deeper into ball games. They’ve dominated the opposing lineups, and that dominance should continue today.
Caesars QuickPick: Our Astros vs Mariners same-game parlay (SGP)
Under 6.5
Hunter Brown Over 7.5 strikeouts
Victor Caratini 1+ total base
Seattle boasts a whopping 25% strikeout rate at home, and Brown has eight or more strikeouts in five of his previous seven starts.
Woo has allowed 10 home runs and a 4.64 xFIP to the left side. Victor Caratini is riding an eight-game hitting streak with a .304 BABIP on the road against righties.
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Astros vs Mariners odds
Astros vs Mariners live odds
Astros vs Mariners opening odds
- Moneyline: Houston -105 | Seattle -115
- Run line: Houston -1.5 (+168) | Seattle +1.5 (-205)
- Over/Under: Over 6.5 (-115) | Under 6.5 (-105)
Odds courtesy of Caesars.
Astros vs Mariners trend
The Astros have hit the game total Under in 36 of their last 65 games (+6.65 Units / 9% ROI). Find more MLB betting trends for Astros vs. Mariners.
How to watch Astros vs Mariners and game info
| Location | T-Mobile Park, Seattle, WA |
| Date | Sunday, 7-20-2025 |
| First pitch | 4:10 p.m. ET |
| TV | SCHN, RSNW |
| Astros starting pitcher | Hunter Brown (9-4, 2.43 ERA) |
| Mariners starting pitcher | Bryan Woo (8-4, 2.75 ERA) |
Astros vs Mariners latest injuries
Astros vs Mariners weather
Odds are correct at the time of publishing and are subject to change.
Not intended for use in MA.
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