Seattle Mariners

Seattle Mariners33-28-0 ATS · 74-66-0 ML · 2021

MLBAmerican • AL West

The Seattle Mariners went 74-66-0 straight up, 33-28-0 ATS (54.1% cover rate), 33-26-2 O/U (55.93% over rate) in 2021, returning +0.62% ROI on flat $100 bets at closing odds. Closing lines from DraftKings, FanDuel, and BetMGM, graded against official MLB box scores.

See methodology.

Seattle Mariners Betting Record — 2021

Against the Spread
33-28-0
Win%
54.1%
ROI
+0.62%
Units
+0.4
Moneyline
74-66-0
Win%
52.86%
ROI
+14.18%
Units
+19.9
Over Rate
33-26-2
Win%
55.93%
ROI
+6.72%
Units
+4.0

Mariners Monthly Performance

+0.8%33-28 · +0.5u
-2.8%
-4.5%
+11.1%
-31.7%
Jul
6-5
Aug
12-11
Sep
14-10
Oct
1-2
Top Betting AngleMin. 10 games
Mariners As Underdog ML: 20-15-0
Win %: 57.14%ROI: +32.01%35 games

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Mariners Home / Away Splits

Home
ATS
12-17-0-22.99%
ML
37-32-0+8.96%
O/U
18-11-0+18.04%
Away
ATS
21-11-0+22%
ML
37-34-0+19.26%
O/U
15-15-2-4.22%

Mariners as Favorite / Underdog

As Favorite
ATS
9-17-0-24%
ML
15-11-0-2.1%
As Underdog
ATS
24-11-0+18.9%
ML
20-15-0+32.01%

Betting Against the Mariners

What happens when you fade the Mariners and bet on their opponent every game?

Fade Against the Spread
28-33-0
Win%
45.9%
ROI
-13.31%
Units
-8.1
Fade Moneyline
66-74-0
Win%
47.14%
ROI
-13.85%
Units
-19.4

Mariners Recent Games

View full schedule

Mariners Player Props

Seattle Mariners Player Prop Performance

Historical hit rates for every Mariners player — hits, home runs, RBIs, strikeouts.

Mariners Head-to-Head Matchups

AL West Standings

MoneylineATSOver/Under
#TeamRecordWin%ROIRecordWin%ROIRecordWin%ROI
1HOU91-66-057.96%-4.57%32-43-042.67%-19.09%37-32-653.62%+1.79%
2SEA74-66-052.86%+14.18%33-28-054.1%+0.62%33-26-255.93%+6.72%
3LAA69-79-046.62%-5.71%29-37-043.94%-14.08%30-34-246.88%-10.25%
4TEX53-91-036.81%-12.88%27-36-042.86%-18.25%32-27-454.24%+4.52%
5OAK

Frequently Asked Questions

What is the Seattle Mariners record against the spread?
The Seattle Mariners were 33-28-0 against the spread in 2021 on DraftKings, with a 54.1% cover rate and +0.62% ROI.
What is the Seattle Mariners home and away ATS record?
At home, the Seattle Mariners were 12-17-0 ATS (-22.99% ROI). On the road, they were 21-11-0 ATS (+22% ROI).
How did the Seattle Mariners performed as favorites vs underdogs ATS?
As favorites, the Seattle Mariners were 9-17-0 ATS (34.62% cover rate). As underdogs, they were 24-11-0 ATS (68.57% cover rate).
What is the Seattle Mariners moneyline record?
The Seattle Mariners were 74-66-0 straight up (moneyline) in 2021, with a 52.86% win rate and +14.18% ROI on DraftKings.

Seattle MarinersBetting Record & ATS Analysis

The Seattle Mariners were 33-28-0 against the spread in 2021 on DraftKings, covering at a 54.1% rate with a +0.62% return on investment for bettors. Their straight-up moneyline record was 74-66-0 (52.86% win rate). Games involving the Mariners went Over at a 55.93% rate.

At home, the Mariners were 12-17-0 ATS (-22.99% ROI). On the road, they were 21-11-0 ATS (+22% ROI). As a favorite, Mariners covered at 34.62%. As an underdog, they covered at 68.57%.

Data sourced from DraftKings closing lines. Updated daily after games are graded. Past performance does not guarantee future results. LineTerminal offers advanced system-building tools to research Seattle Mariners betting trends across 80+ filters and 5+ years of data.

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