Seattle Mariners vs Tampa Bay Rays Prediction – 9/1/2025
The Seattle Mariners pulled off a three-game sweep the last time the Mariners and Tampa Bay Rays met. Seattle will look for a similar result on the road this time around as Seattle and Tampa will do battle on Monday night in Tampa. Before this game with huge playoff implications, continue reading to get my breakdown of this matchup and to get my Mariners vs Rays prediction for tonight.
Our Mariners vs Rays Pick
- Pick: Mariners Moneyline
- Confidence: ★★★☆☆
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Game Snapshot
- Matchup: Seattle Mariners vs Tampa Bay Rays
- Date & Time: Monday, September 1, 2025, 7:35 p.m. ET
- Starting Pitchers:
- Mariners – Luis Castillo (8-7, 3.75 ERA)
- Rays – Shane Baz (8-11, 5.19 ERA)
- Stadium: George M. Steinbrenner Field, Tampa, FL
- Broadcast: FDSSUN and ROOT Sports NW
Key Storylines
Pitching Matchup
Luis Castillo enters tonight’s start with a solid 3.75 ERA through 28 starts and 133 strikeouts in 151.1 innings. But he’s allowed 14 runs over his last 13 innings and there is some concern about his recent performance. Shane Baz will get the start for Tampa Bay. He enters this game with a 5.19 ERA across 27 starts. He’s been inconsistent and susceptible to home runs and walks this season.
Key Players
Seattle’s Cal Raleigh leads the team with 50 homers and 107 RBI. Julio Rodríguez is on a seven-game hitting streak and batting .368 over the last 10 games. Josh Naylor and Eugenio Suárez offer additional offensive firepower. The Rays will rely on Junior Caminero (39 HRs, 94 RBIs), Yandy Díaz (.284 average), and Brandon Lowe (28 HRs) to supply offense in this matchup.
Recent Team Streaks
- The Mariners lost two out of three games against the Cleveland Guardians in their most recent series.
- Tampa earned a three-game sweep of the Washington Nationals in their last series.
Best Player Props
| Player | Prop |
|---|---|
| Cal Raleigh | Over 0.5 Home Runs |
| Julio Rodríguez | Over 1.5 Total Bases |
| Shane Baz | Under 5.5 Strikeouts |
| Luis Castillo | Over 5.5 Strikeouts |
Betting Trends & H2H
- Seattle is 3-0 against the Rays so far this season.
- The Mariners won by 2+ runs in two of their three wins over the Rays this year.
- Seattle is 32-37 on the road this season.
- Tampa is 34-33 at home in 2025.
Mariners vs Rays Model Projection
Score Projection: Mariners 5 – Rays 4
Win Probability: Mariners 55%, Rays 45%
Final Thoughts
Both starting pitchers have had their share of struggles lately for their respective teams. But the ceiling is higher for Luis Castillo right now than it is for Shane Baz. Seattle should get a win tonight to help their chances in the AL West race against the Houston Astros. I recommend playing Seattle on the moneyline, while more risk-tolerant bettors may want to back Seattle on the runline.
