Seattle Mariners Lead Kansas City Royals 20-13 in Head-to-Head Matchups

MLB15-18-0 ATS (45.45%)Data through 2025-09-18

Mariners vs Royals Betting Record

Against the Spread
15-18-0
Win %
45.45%
ROI
-3.63%
Units
-1.2
Moneyline
20-13-0
Win %
60.61%
ROI
-0.46%
Units
-0.1
Over Rate
20-12-1
Win %
62.5%
ROI
+19.74%
Units
+6.3

From the Other Side — Royals vs Mariners

Against the Spread
18-15-0
Win %
54.55%
ROI
+0.9%
Units
+0.3
Moneyline
13-20-0
Win %
39.39%
ROI
-13.96%
Units
-4.6
Over Rate
20-12-1
Win %
62.5%
ROI
+19.74%
Units
+6.3

Venue Splits

Mariners Home
8-9-0 ATS
47.06% • +2.1%
11-6-0 ML (64.71%)
Royals Home
9-7-0 ATS
56.25% • +10.29%
7-9-0 ML (43.75%)

Scoring Averages

Mariners
5.7
PPG
4.7
allowed
Total
10.5
Avg
33
games
Royals
4.7
PPG
5.7
allowed

Recent Matchups

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
06/09W 5-6WO
06/08L 8-4LO
06/07L 10-9LO
05/15W 4-2WU
05/14L 2-4LU
05/13W 6-2WO
08/27W 3-2WU
08/26W 15-2WO
08/25W 7-5WO
08/17W 4-6WO
08/16W 5-6WO
08/15W 8-10WO
08/14L 7-6LO

Frequently Asked Questions

What is the Seattle Mariners vs Kansas City Royals all-time record?
The Seattle Mariners are 20-13 against the Kansas City Royals in head-to-head matchups.
What is the Seattle Mariners ATS record vs the Kansas City Royals?
The Seattle Mariners are 15-18-0 against the spread vs the Kansas City Royals on DraftKings, with -3.63% ROI.
Do Seattle Mariners vs Kansas City Royals games go over or under?
Seattle Mariners vs Kansas City Royals games average 10.5 total points. The Over has hit 62.5% of the time.

More Mariners Matchups

Head-to-head betting record for Seattle Mariners vs Kansas City Royals on LineTerminal. The Mariners are 20-13 straight up against the Royals and 15-18-0 against the spread (45.45% cover rate, -3.63% 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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