MLB Prediction: St. Louis Cardinals vs Seattle Mariners (Wednesday, September 10 at 09:40 PM ET)
Introduction
| Market / Trend | STL | SEA |
|---|---|---|
| Moneyline | +185 | -227 |
| Total (O/U) | 7.5 | |
| Run Line | +1.5 (-115) | -1.5 (-105) |
| Last 5 RPG | 2.8 | 7.6 |
| Record | 72–73 | 76–68 |
| Lines: BetMGM, BetOnline.ag, BetRivers, BetUS +7 more | ||
More MLB picks: St. Louis Cardinals · Seattle Mariners
Seattle Mariners’ offense has surged to 7.6 runs per game across the last five, but the sharper MLB prediction here points toward St. Louis leveraging steadier situational value. The Cardinals’ recent 2–3 stretch has masked competitive balance, with their lineup anchored by multiple consistent contact hitters. This interleague matchup between the American League Mariners and the National League Cardinals sets up as a high‑variance contest where the underdog’s bats are positioned to break through, and the scoring profile leans clearly toward the Over.
Game Time
Scheduled for Wednesday, September 10 at 09:40 PM ET at T-Mobile Park, pitcher-friendly by profile.
Odds & Spread Line
- St. Louis Cardinals: +185
- Seattle Mariners: -227
Total: 7.5
- Run Line — St. Louis Cardinals: +1.5 (-115)
- Run Line — Seattle Mariners: -1.5 (-105)
Latest Team Records
St. Louis Cardinals: 72-73 (Win %: 0.497)
Seattle Mariners: 76-68 (Win %: 0.528)
Injury Report
The St. Louis Cardinals are currently healthy with no major injury concerns.
Seattle Mariners are missing Logan Evans (Elbow), listed as 15-Day-IL; Ryan Bliss (Knee), listed as 60-Day-IL.
Key Player Stats
St. Louis Cardinals
- Willson Contreras: 0.254 AVG, 20 HR, 78 RBI
- Alec Burleson: 0.286 AVG, 17 HR, 62 RBI
- Ivan Herrera: 0.283 AVG, 14 HR, 55 RBI
Seattle Mariners
- Cal Raleigh: 0.242 AVG, 53 HR, 113 RBI
- Eugenio Suarez: 0.236 AVG, 45 HR, 109 RBI
- Julio Rodriguez: 0.268 AVG, 30 HR, 90 RBI
Team Analysis
St. Louis Cardinals
The Cardinals’ recent mark of 2-3 (2.8 RPG) emphasizes inconsistency, but their offense remains capable of timely production. Willson Contreras has been a stabilizing presence in the middle of the order, keeping the lineup competitive even when run totals dip. This club has shown resilience on the road despite a sub-.500 away record, and that experience in tight games makes them a live underdog in this spot.
Across the last 10 games at 5-5 (3.2 RPG), the Cardinals have balanced modest scoring with enough pitching stability to stay within striking distance. Alec Burleson and Ivan Herrera provide depth that prevents opposing staffs from working around one bat, a key factor against a Mariners rotation that can be exploited. With consistent contact and situational hitting, St. Louis is positioned to convert limited chances into run support that matters late.
- Batting Average: 0.245
- Total Runs Scored: 627
- Home Runs: 137
- OBP: 0.314
- SLG: 0.38
- OPS: 0.693
- ERA: 4.28
- WHIP: 1.31
Away Record: 31-40 • Home Record: 41-34
Last 5 Games: 2-3 (2.8 RPG)
Last 10 Games: 5-5 (3.2 RPG)
Seattle Mariners
The Mariners’ recent surge of 4-1 (7.6 RPG) shows their lineup firing, with Cal Raleigh setting the tone through power production. Their season-long home record of 43-27 demonstrates comfort at this venue, but the offensive spike is not guaranteed to hold against disciplined pitching. While their record suggests strength, reliance on big swings can leave them vulnerable to streaky stretches.
Over the last 10 contests at 5-5 (5.6 RPG), Seattle has alternated between explosive scoring and quieter outings. Eugenio Suarez and Julio Rodriguez contribute power upside, but the Mariners’ rhythm has leaned on bursts rather than consistent run creation. Against a Cardinals team that thrives when keeping games close, Seattle Mariners’ volatility makes them a less reliable side despite the recent strong scoring.
- Batting Average: 0.243
- Total Runs Scored: 676
- Home Runs: 212
- OBP: 0.32
- SLG: 0.416
- OPS: 0.736
- ERA: 3.99
- WHIP: 1.25
Away Record: 34-41 • Home Record: 43-27
Last 5 Games: 4-1 (7.6 RPG)
Last 10 Games: 5-5 (5.6 RPG)
Head-to-Head History
Seattle Mariners lead 2–0 (Last 2 games)
- September 09, 2025: STL 3 @ SEA 5
- September 08, 2025: STL 2 @ SEA 4
Over/Under Trends
St. Louis Cardinals’ last 10 games have averaged 7.6 total runs, with 4 games that would have cleared today’s total of 7.5.
Seattle Mariners’ last 10 games have averaged 10.0 combined runs, with 6 games clearing the same number of 7.5.
Moneyline Betting Prediction
The Cardinals’ balanced 5-5 stretch and ability to win on the road despite a tough schedule position them as the sharper play against a Mariners team leaning on volatile scoring. With Contreras, Burleson, and Herrera anchoring a lineup that can manufacture runs in tight games, St. Louis projects as the smarter side to back in this matchup.
The St. Louis Cardinals at +185 fit a live underdog profile on recent numbers.
Over/Under Prediction
Recent five-game scoring: the Seattle Mariners are at 7.6 RPG and the St. Louis Cardinals at 2.8 — a useful baseline against the total.
These teams are combining for 10.4 runs per game recently — above the posted total of 7.5. That points toward the Over 7.5.
Bookmakers
Current MLB odds sourced from: FanDuel, LowVig.ag, BetOnline.ag, Caesars, DraftKings, MyBookie.ag, Bovada, BetMGM, BetRivers, BetUS, Fanatics.
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MLB Predictions FAQ
How does Parlamaz make St. Louis Cardinals vs Seattle Mariners MLB predictions?
We use trusted data feeds and real-time odds to model each matchup. We weight the numbers that move lines—team form, matchup history, injuries, park factors, totals trends, and betting momentum—then compare our price to the market to find value. All signal, no noise. No paywalls.
How should I size my bets?
Use a consistent unit (about 1–2% of bankroll). Singles should be most of your volume. We like parlays—smart ones. Keep legs tight (2–3), cap risk to 0.25–0.5u, and pass when the price isn’t there.
