Seattle Mariners vs Philadelphia Phillies Prediction – 8/20/2025
The Seattle Mariners will look to salvage a game from their three-game series with the Philadelphia Phillies on Wednesday afternoon. The Phillies have won the first two games of this series and will look to complete a sweep of Seattle. But Philadelphia will need to get the better of a very good starting pitcher to do that. Before first pitch from Philly, keep reading to get my Mariners vs Phillies prediction for today’s game.
Our Mariners vs Phillies Pick
- Pick: Over 8.5
- Confidence: 3/5
- Claim Your Bonus Bets: Bet $5 and get $200 in bonus bets INSTANTLY and save over $200 on NFL Sunday Ticket using our DraftKings Sportsbook bonus. Click the Claim Bonus button below to get started!
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 Philadelphia Phillies
- Date & Time: Wednesday, August 20, 2025, 1:05 p.m. ET
- Starting Pitchers: Luis Castillo vs Jesús Luzardo
- Stadium: Citizens Bank Park, Philadelphia, PA
- Broadcast: MLB Network
Key Storylines
Pitching matchup
Luis Castillo brings steadiness to the mound for Seattle. He is 8-6 with a 3.48 ERA for the season. Castillo’s ability to induce groundballs could be a benefit against a Phillies lineup with so many power hitters. Jesus Luzardo has been a feast-or-famine pitcher of late. He’s given up anywhere from zero to eight earned runs in his 13 starts since early June. His variance makes him volatile but his upside is undeniable on the bump.
Key Players
- Kyle Schwarber hit another home run for the Phillies in their win over Seattle last night. He is up to 44 on the season.
- Both Randy Arozarena and Eugenio Suarez had RBI doubles for the Mariners on Tuesday and will look to contribute more extra-base hits today.
Recent team streaks
The Mariners have dropped their last four games and are a game and a half back of the Houston Astros in the AL West standings. The Phillies have won three games in a row and four of their last five heading into this series finale.
Best Player Props
| Player | Prop |
|---|---|
| Kyle Schwarber | 1+ Home Runs |
| Cal Raleigh | 2+ Total Bases |
| Bryce Harper | 2+ Total Bases |
| Luis Castillo | Over 5.5 Strikeouts |
Betting Trends & H2H
- The Phillies lead the season series 2-0 over the Mariners in 2025.
- This is the last game to be played by these teams in the regular season.
- The over is 2-0 in games played between Seattle and Philadelphia this season.
Mariners vs Phillies Model Projection
Score Projection: Phillies 5 – Mariners 4
Win Probability: Phillies 54%, Mariners 46%
Final Thoughts
Both of these teams have managed to make an impact offensively in this series. Philadelphia has certainly had the better of things at the plate through the first two games but Seattle is more than capable of changing that here. No matter who ends up winning this game, I think the best bet for this contest is to take the over. We should see a third straight game between these teams go over the total thanks to all of the home run power on both sides.
