Seattle Mariners Lead Kansas City Royals 4-3 in Head-to-Head Matchups (2025)

MLB4-3-0 ATS (57.14%)Data through 2025-09-18

Mariners vs Royals Betting Record — 2025

Against the Spread
4-3-0
Win %
57.14%
ROI
+18.68%
Units
+1.3
Moneyline
4-3-0
Win %
57.14%
ROI
-2.8%
Units
-0.2
Over Rate
4-3-0
Win %
57.14%
ROI
+5.17%
Units
+0.4

From the Other Side — Royals vs Mariners

Against the Spread
3-4-0
Win %
42.86%
ROI
-17.44%
Units
-1.2
Moneyline
3-4-0
Win %
42.86%
ROI
-15.95%
Units
-1.1
Over Rate
4-3-0
Win %
57.14%
ROI
+5.17%
Units
+0.4

Venue Splits

Mariners Home
2-2-0 ATS
50% • -5.07%
2-2-0 ML (50%)
Royals Home
1-2-0 ATS
33.33% • -12%
1-2-0 ML (33.33%)

Scoring Averages

Mariners
4.7
PPG
3.6
allowed
Total
8.3
Avg
7
games
Royals
3.6
PPG
4.7
allowed

Recent Matchups (2025)

DateScoreATSMLO/U
09/18W 0-2WU
09/17L 7-5LO
09/16W 5-12WO
07/03L 2-3LU
07/02W 3-2WU
07/01L 3-6LO
06/30W 6-2WO

Frequently Asked Questions

What is the Seattle Mariners vs Kansas City Royals all-time record?
The Seattle Mariners are 4-3 against the Kansas City Royals in 2025 in head-to-head matchups.
What is the Seattle Mariners ATS record vs the Kansas City Royals?
The Seattle Mariners are 4-3-0 against the spread vs the Kansas City Royals in 2025 on DraftKings, with +18.68% ROI.
Do Seattle Mariners vs Kansas City Royals games go over or under?
Seattle Mariners vs Kansas City Royals games average 8.3 total points in 2025. The Over has hit 57.14% of the time.

More Mariners Matchups

Head-to-head betting record for Seattle Mariners vs Kansas City Royals in the 2025 season on LineTerminal. The Mariners are 4-3 straight up against the Royals and 4-3-0 against the spread (57.14% cover rate, +18.68% ROI) on DraftKings. Data sourced from DraftKings closing lines. Updated daily after games are graded. Past performance does not guarantee future results.

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