• The Red Sox are -170 favorites vs the Mariners
• Mariners vs Red Sox Over / Under today: 7.5 Runs
• Mariners / Red Sox TV Channel: NESN | MRTV

The Seattle Mariners (+140) visit Fenway Park to take on the Boston Red Sox (-170) on August 31, 2026. First pitch is scheduled for 6:45 pm in Boston, MA.

This season, the Mariners are against the spread (ATS), while the Red Sox are ATS.

Mariners vs Red Sox Starting Pitchers Today:

• Mariners starting pitcher: George Kirby 9-10, 4.04 ERA
• Red Sox starting pitcher: Payton Tolle 8-6, 3.11 ERA

Mariners vs. Red Sox Odds, Run Line, Over/Under & Moneyline

Mariners vs Red Sox Prediction for Today’s Game

Based on recent trends the model predicts the Red Sox will win Monday‘s MLB game with 55.4% confidence, factoring in game simulations, recent player performances, starting pitchers and injuries.

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We’ve highlighted some favorite MLB player prop bets for Mariners players for Monday‘s game, looking at profitable historical betting trends:

Best Mariners Player Prop Bets Today:

• J.P. Crawford has hit the Walks Under in 22 of his last 25 away games (+16.95 Units / 40% ROI)
• Weston Wilson has hit the Home Runs Over in 3 of his last 10 away games (+16.50 Units / 165% ROI)
• George Kirby has hit the Hits Allowed Over in 20 of his last 25 games (+15.55 Units / 52% ROI)
• Cal Raleigh has hit the Hits Runs and RBIs Under in 20 of his last 25 away games (+13.55 Units / 40% ROI)
• Cal Raleigh has hit the Runs Under in 17 of his last 20 away games (+11.75 Units / 34% ROI)

And here are some favorite MLB player prop bets for Red Sox players for Monday‘s game, looking at profitable historical betting trends:

Best Red Sox Player Prop Best Bets Today:

• Nick Sogard has hit the Home Runs Over in 2 of his last 4 games at home (+22.00 Units / 550% ROI)
• Wilyer Abreu has hit the Walks Over in 16 of his last 25 games (+17.60 Units / 70% ROI)
• Nick Sogard has hit the Hits Runs and RBIs Over in 15 of his last 20 games at home (+10.10 Units / 43% ROI)
• Nick Sogard has hit the Hits Over in 16 of his last 20 games at home (+10.05 Units / 26% ROI)
• Ceddanne Rafaela has hit the Runs Under in his last 10 games (+10.00 Units / 62% ROI)

Mariners Best Bets Today:

• The Seattle Mariners have hit the Game Total Over in 28 of their last 45 away games (+11.85 Units / 24% ROI)
• The Seattle Mariners have hit the Team Total Under in 25 of their last 40 away games (+8.60 Units / 19% ROI)
• The Seattle Mariners have hit the 1st Five Innings (F5) Team Total Over in 10 of their last 15 games (+4.60 Units / 25% ROI)
• The Seattle Mariners have covered the 1st Five Innings (F5) Run Line in 7 of their last 12 away games (+1.00 Units / 6% ROI)
• The Seattle Mariners have hit the 1st Five Innings (F5) Moneyline in 8 of their last 16 games (+0.80 Units / 4% ROI)

Red Sox Best Bets Today:

• The Boston Red Sox have hit the Moneyline in 35 of their last 50 games (+15.05 Units / 21% ROI)
• The Boston Red Sox have hit the 1st Five Innings (F5) Team Total Over in 30 of their last 45 games at home (+14.40 Units / 27% ROI)
• The Boston Red Sox have covered the Run Line in 28 of their last 50 games (+11.40 Units / 20% ROI)
• The Boston Red Sox have hit the Team Total Over in 21 of their last 30 games at home (+11.05 Units / 31% ROI)
• The Boston Red Sox have covered the 1st Five Innings (F5) Run Line in 20 of their last 30 games at home (+9.45 Units / 28% ROI)

Mariners Against the Spread (ATS) Record

Against the spread this season, the Mariners are against the Run Line ( Units / ROI).

• away moneyline record when betting on the Moneyline for ML units Units / ML ROI ROI
• away total over record when betting on the total runs Over for over units Units / over ROI ROI
• away total under record when betting on the total runs Under for under units Units / under ROI ROI

Red Sox Against the Spread (ATS) Record

Against the spread this season, the Red Sox are against the Run Line ( Units / ROI).

• home moneyline record when betting on the Moneyline for ML units Units / ML ROI ROI
• home total over record when betting on the total runs Over for over units Units / over ROI ROI
• home total under record when betting on the total runs Under for under units Units / under ROI ROI

Red Sox vs Mariners Home Run Prop Bets Today

Red Sox vs Mariners Total Hits Prop Bets Today

Red Sox vs Mariners Strikeout Prop Bets Today

Mariners Keys to the Game vs. the Red Sox

The Mariners are just 22-34 (.393) vs bottom 10 scoring offenses this season Today, they face the Red Sox (15th in runs scored).

The Mariners are 9-4 (.692) when tied entering the 8th inning this season — 2nd best in MLB.

The Mariners are just 2-66 (.029) when trailing entering the 9th inning this season — tied for 3rd lowest in MLB.

The Mariners are just 2-63 (.031) when trailing entering the 8th inning this season — 3rd lowest in MLB.

Red Sox Keys to the Game vs. the Mariners

The Red Sox are 55-5 (.917) when leading entering the 7th inning this season — 5th best in MLB.

The Red Sox are 63-2 (.969) when leading entering the 8th inning this season — 3rd best in MLB.

The Red Sox are just 6-36 (.143) when allowing 5 or more runs this season — 5th lowest in MLB.

The Red Sox are 44-30 (.595) after a win this season — 3rd best in MLB.

Mariners Hitting Stats & Trends

The Mariners are batting just .227 this season — lowest in MLB.

Mariners hitters are slugging just .476 on the first pitch of at-bats this season — lowest in MLB.

The Mariners are just 19-37 (.339) against the run line (-22.2% ROI) vs bottom 10 scoring offenses this season Today, they face the Red Sox (15th in runs scored).

The Mariners are batting just .213 against LHP this season — lowest in MLB.

Red Sox Hitting Stats & Trends

The Red Sox are batting .284 in lefty-lefty matchups this season — 2nd best in MLB.

Red Sox hitters have an OPS of .767 (1,352 PA’s) against LHP this season — 4th best in MLB.

The Red Sox are batting .257 against LHP this season — 4th best in MLB.

Red Sox hitters are slugging .432 against LHP this season — 4th best in MLB.

Mariners Pitching Stats & Trends

Mariners pitchers have walked 7% of batters this season — 2nd best in MLB.

Mariners pitchers have thrown at least two strikes in their first three pitches to 69% of opposing batters this season — highest in MLB.

Mariners pitchers have a first-pitch strike rate of 66% this season — highest in MLB.

The Mariners pitchers have allowed division opponents to score first in just 36% of their games this season — lowest in MLB.

Red Sox Pitching Stats & Trends

Red Sox pitchers have walked 6% of batters when facing the leadoff batter in the inning this season — tied for 2nd best in MLB.

Red Sox pitchers have walked 8% of batters this season — 3rd best in MLB.

Red Sox pitchers have an ERA of 3.55 (615.1 IP) on the road this season — 2nd best in MLB.

Red Sox pitchers have allowed an exit velocity of 95 MPH or greater 1,166 times this season — 3rd fewest in MLB.

More MLB Reading:

• Home Run Predictions Today
• Best NRFI Bets Today
• Strikeout Props Today
• MLB Starting Pitchers Today

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