The Seattle Mariners will aim to extend their lead in the AL West as they face the Houston Astros at Daikin Park on Saturday. After a dominant 4–0 victory in the series opener, Seattle holds a one-game advantage over Houston in the AL West standings. Here, we break down this huge matchup on Saturday night, and you can find my Mariners vs Astros prediction below.
Our Mariners vs Astros Pick
- Pick: Astros Moneyline
- Confidence: 4/5
- Get Your Bonus Bets: Bet $5 and get $200 in bonus bets INSTANTLY using our DraftKings Sportsbook bonus. Click the Claim Bonus button below to start!
Bet $5, Get $200 in Bonus Bets Instantly + Over $200 Off NFL Sunday Ticket
Gambling Problem? Call or TEXT 1-800-Gambler 21+ 
Gambling Problem? Call or TEXT 1-800-Gambler 21+
Promo Code: Click To Claim
Bet $5, Get $200 in Bonus Bets Instantly + Over $200 Off NFL Sunday Ticket
Gambling Problem? Call or TEXT 1-800-Gambler 21+
Promo Code: Click To Claim
Gambling Problem? Call or TEXT 1-800-Gambler 21+
Game Snapshot
- Matchup: Seattle Mariners vs Houston Astros
- Date & Time: Saturday, September 20, 2025, 7:10 PM EDT
- Starting Pitchers: George Kirby (SEA) vs Framber Valdez (HOU)
- Stadium: Daikin Park, Houston, TX
- Broadcast: ROOT Sports NW (Seattle), Space City Home Network (Houston)
Key Storylines
Pitching Matchup
George Kirby (9–7, 4.46 ERA) takes the mound for the Mariners. Despite a solid season, Kirby has struggled in previous outings at Daikin Park, including a game where he allowed five runs in his 2025 debut there. He’ll need to adjust to the Astros’ potent lineup to keep Seattle in contention.
Framber Valdez (12–10, 3.59 ERA) has been a reliable force for Houston. With 173 strikeouts over 180.1 innings, Valdez brings consistency and experience to the mound. His ability to control the game will be important for the Astros’ chances of evening things up in the AL West.
Recent Team Streaks
- Mariners: Seattle enters the game on a 12–1 run propelling them to the top of the AL West.
- Astros: Houston had a three-game winning streak snapped by the Mariners last night.
Best Player Props
| Player | Prop |
|---|---|
| Julio Rodríguez | Over 0.5 Home Runs |
| Cal Raleigh | Over 0.5 Home Runs |
| Framber Valdez | Over 6.5 Strikeouts |
| George Kirby | Over 5.5 Strikeouts |
Betting Trends & H2H
- Mariners: 12–1 in their last 13 games, demonstrating strong form.
- Astros: 6–4 in their last 10 games, with recent struggles against top-tier teams.
- Head-to-Head: Mariners lead the season series 6–5, indicating a competitive matchup.
Mariners vs Astros Model Projection
- Score Projection: Mariners 4 – Astros 5
- Win Probability: Mariners 48%, Astros 52%
Final Thoughts
With both teams in a tight race for the AL West title, every game is critical. Seattle’s recent surge and Houston’s home-field advantage set the stage for an exciting matchup. I think that the Astros have the best chance to win this game at home. Valdez has been electric this season and he should continue to be electric in this contest. I’ll take the Astros to get the win at home and to draw level in the AL West race heading into Sunday’s series finale between these teams.
