MLB Prediction: St. Louis Cardinals vs Seattle Mariners (Tuesday, September 9 at 09:40 PM ET)
Introduction
| Market / Trend | STL | SEA |
|---|---|---|
| Moneyline | +165 | -200 |
| Total (O/U) | 7.5 | |
| Run Line | +1.5 (-123) | -1.5 (103) |
| Last 5 RPG | 3.2 | 7.4 |
| Record | 72–72 | 75–68 |
| Lines: BetMGM, BetOnline.ag, BetRivers, BetUS +7 more | ||
More MLB picks: St. Louis Cardinals · Seattle Mariners
Seattle Mariners’ last 10 contests have averaged 10.1 total runs, setting the stage for an interleague MLB prediction where run production takes center focus. The Cardinals’ balanced offense has kept them competitive across their last 10 with a 6-4 record, while the Mariners have been less consistent at 4-6 despite strong home numbers. This matchup analysis points toward St. Louis leveraging steadier form and capitalizing on Seattle Mariners’ uneven rhythm to deliver value on both the moneyline and total.
Game Time
This one goes at Tuesday, September 9 at 09:40 PM ET inside T-Mobile Park, unders stay live.
Odds & Spread Line
- St. Louis Cardinals: +165
- Seattle Mariners: -200
Total: 7.5
- Run Line — St. Louis Cardinals: +1.5 (-123)
- Run Line — Seattle Mariners: -1.5 (+103)
Latest Team Records
St. Louis Cardinals: 72-72 (Win %: 0.5)
Seattle Mariners: 75-68 (Win %: 0.524)
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, 16 HR, 60 RBI
- Ivan Herrera: 0.283 AVG, 14 HR, 55 RBI
Seattle Mariners
- Cal Raleigh: 0.243 AVG, 53 HR, 113 RBI
- Eugenio Suarez: 0.238 AVG, 45 HR, 109 RBI
- Julio Rodriguez: 0.267 AVG, 30 HR, 89 RBI
Team Analysis
St. Louis Cardinals
The Cardinals have steadied their rhythm with a 3-2 mark over the last five games, averaging 3.2 runs per contest. While that number points to modest offensive output, their overall 6-4 stretch across the last 10 highlights improvement and the ability to edge opponents in tighter matchups. Willson Contreras adds veteran balance to the lineup, ensuring consistent production even in lower-scoring environments.
Road form at 31-39 is not elite, but it has shown enough competitive resilience to keep them in games, particularly against inconsistent opponents. Alec Burleson and Ivan Herrera provide complementary hitting, giving this lineup depth beyond a single power source. With steadier recent results than Seattle, the Cardinals project as the sharper side in this interleague spot.
- Batting Average: 0.245
- Total Runs Scored: 624
- Home Runs: 137
- OBP: 0.314
- SLG: 0.38
- OPS: 0.694
- ERA: 4.27
- WHIP: 1.31
Away Record: 31-39 • Home Record: 41-34
Last 5 Games: 3-2 (3.2 RPG)
Last 10 Games: 6-4 (3.6 RPG)
Seattle Mariners
The Mariners’ recent 3-2 stretch has been powered by a surging 7.4 runs per game, but their broader 4-6 record across the last 10 exposes inconsistency. Cal Raleigh’s power numbers carry weight, yet the lineup as a whole hasn’t translated big outputs into consistent wins. That uneven form, even with strong home support, leaves them vulnerable against a steadier opponent.
Seattle Mariners’ 42-27 home record signals comfort at this venue, but recent scoring volatility makes them less trustworthy for bettors. Julio Rodriguez offers athletic upside, while Eugenio Suarez adds power, yet the collective rhythm has not been sustained. When paired against a Cardinals team that’s been more efficient in close games, Seattle Mariners’ recent form looks less reliable despite their offensive bursts.
- Batting Average: 0.243
- Total Runs Scored: 671
- Home Runs: 210
- OBP: 0.319
- SLG: 0.415
- OPS: 0.735
- ERA: 4.0
- WHIP: 1.25
Away Record: 34-41 • Home Record: 42-27
Last 5 Games: 3-2 (7.4 RPG)
Last 10 Games: 4-6 (5.5 RPG)
Head-to-Head History
Seattle Mariners lead 1–0 (Most recent game)
- September 08, 2025: STL 2 @ SEA 4
Over/Under Trends
St. Louis Cardinals’ last 10 games have averaged 8.0 total runs, with 4 games that would have cleared today’s total of 7.5.
Seattle Mariners’ last 10 games have averaged 10.1 combined runs, with 6 games clearing the same number of 7.5.
Moneyline Betting Prediction
The Cardinals’ 6-4 stretch across their last 10, combined with steadier offensive balance from Contreras, Burleson, and Herrera, makes them the sharper side against Seattle Mariners’ inconsistent rhythm. With the Mariners failing to convert recent scoring surges into wins, St. Louis projects as the more reliable moneyline play in this interleague matchup.
We rate the St. Louis Cardinals at +165 as the right side at current form.
Over/Under Prediction
In their last five, the Seattle Mariners have produced 7.4 RPG and the St. Louis Cardinals 3.2. That output frames how this total sets up.
These teams are combining for 10.6 runs per game recently — above the posted total of 7.5. That points toward the Over 7.5.
Bookmakers
Shop the MLB odds at: FanDuel, LowVig.ag, MyBookie.ag, BetOnline.ag, Caesars, DraftKings, Bovada, BetMGM, BetRivers, BetUS, Fanatics.
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MLB Predictions FAQ
What do moneyline, run line, and total mean?
Moneyline is who wins the game. Run line is a spread, usually ±1.5 runs. The total (over/under) is combined runs by both teams.
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.
