• The Cubs are -110 favorites vs the Mariners
• Cubs vs Mariners Over / Under today: 8 Runs
• Cubs / Mariners TV Channel: MARQ | MRTV | KING

The Chicago Cubs (-110) visit T-Mobile Park to take on the Seattle Mariners (-110) on August 21, 2026. First pitch is scheduled for 10:10 pm in Seattle, WA.

This season, the Cubs are 74-54 against the spread (ATS), while the Mariners are 48-79 ATS.

Cubs vs Mariners Starting Pitchers Today:

• Cubs starting pitcher: Matthew Boyd 8-2, 4.08 ERA
• Mariners starting pitcher: Emerson Hancock 7-7, 3.32 ERA

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

Cubs vs Mariners Prediction for Today’s Game

Based on recent trends the model predicts the Mariners will win Friday‘s MLB game with 51.0% 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 Cubs players for Friday‘s game, looking at profitable historical betting trends:

Best Cubs Player Prop Bets Today:

• Tyrone Taylor has hit the Home Runs Over in 3 of his last 6 away games (+21.50 Units / 358% ROI)
• Seiya Suzuki has hit the RBIs Over in 12 of his last 20 away games (+12.35 Units / 62% ROI)
• Pete Crow-Armstrong has hit the Singles Under in 16 of his last 20 away games (+10.60 Units / 41% ROI)
• Michael Busch has hit the Runs Under in 16 of his last 20 games (+10.20 Units / 32% ROI)
• Pete Crow-Armstrong has hit the Hits Under in 9 of his last 10 games (+9.40 Units / 48% ROI)

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

Best Mariners Player Prop Best Bets Today:

• Cal Raleigh has hit the Runs Under in 21 of his last 25 games (+13.95 Units / 32% ROI)
• Cal Raleigh has hit the Total Bases Under in 18 of his last 25 games at home (+11.45 Units / 39% ROI)
• Randy Arozarena has hit the Home Runs Over in 3 of his last 9 games (+10.50 Units / 117% ROI)
• Cal Raleigh has hit the Hits Runs and RBIs Under in 18 of his last 25 games (+10.10 Units / 30% ROI)
• Dominic Canzone has hit the RBIs Under in his last 10 games at home (+10.00 Units / 43% ROI)

Cubs Best Bets Today:

• The Chicago Cubs have covered the Run Line in 31 of their last 50 games (+18.80 Units / 32% ROI)
• The Chicago Cubs have hit the Moneyline in 22 of their last 30 away games (+13.65 Units / 38% ROI)
• The Chicago Cubs have hit the Team Total Over in 21 of their last 30 away games (+10.55 Units / 30% ROI)
• The Chicago Cubs have hit the 1st Five Innings (F5) Team Total Over in 19 of their last 30 away games (+6.40 Units / 17% ROI)
• The Chicago Cubs have hit the Game Total Over in 8 of their last 12 away games (+4.70 Units / 36% ROI)

Mariners Best Bets Today:

• The Seattle Mariners have hit the 1st Five Innings (F5) Team Total Under in 28 of their last 45 games at home (+9.70 Units / 18% ROI)
• The Seattle Mariners have hit the Team Total Under in 27 of their last 45 games at home (+8.75 Units / 17% ROI)
• The Seattle Mariners have hit the Game Total Over in 20 of their last 35 games (+7.90 Units / 20% ROI)
• The Seattle Mariners have covered the 1st Five Innings (F5) Run Line in 6 of their last 9 games (+2.35 Units / 21% ROI)
• The Seattle Mariners have hit the Moneyline in 4 of their last 7 games (+1.60 Units / 23% ROI)

Cubs Against the Spread (ATS) Record

Against the spread this season, the Cubs are 61-65 against the Run Line (-0.45 Units / -0.3% ROI).

• 74-54 when betting on the Moneyline for +4.85 Units / 2.8% ROI
• 68-58 when betting on the total runs Over for +4.9 Units / 3.48% ROI
• 58-68 when betting on the total runs Under for -16.3 Units / -11.57% ROI

Mariners Against the Spread (ATS) Record

Against the spread this season, the Mariners are 48-79 against the Run Line (-27.2 Units / -18.55% ROI).

• 60-68 when betting on the Moneyline for -24.1 Units / -14.17% ROI
• 64-57 when betting on the total runs Over for +1.5 Units / 1.06% ROI
• 57-64 when betting on the total runs Under for -13.15 Units / -9.35% ROI

Mariners vs Cubs Home Run Prop Bets Today

Mariners vs Cubs Total Hits Prop Bets Today

Mariners vs Cubs Strikeout Prop Bets Today

Cubs Keys to the Game vs. the Mariners

The Cubs are 18-22 (.450) when allowing 10 or more hits this season — best in MLB.

The Cubs are 28-28 (.500) when allowing 2 or more home runs this season — best in MLB.

The Cubs are 39-4 (.907) when they’ve had 10 or more hits this season — best in MLB.

The Cubs are 27-6 (.818) when they’ve scored in the first inning this season — best in MLB.

Mariners Keys to the Game vs. the Cubs

The Mariners are just 1-58 (.017) when trailing entering the 8th inning this season — tied for lowest in MLB.

The Mariners are just 17-20 (.459) when they’ve scored in the first inning this season — tied for lowest in MLB.

The Mariners are just 22-31 (.415) vs bottom 10 scoring offenses this season Today, they face the Cubs (second in runs scored).

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

Cubs Hitting Stats & Trends

The Cubs are 18-22 (.450) when allowing 10 or more hits this season — best in MLB.

The Cubs are 28-28 (.500) when allowing 2 or more home runs this season — best in MLB.

The Cubs are 39-4 (.907) when they’ve had 10 or more hits this season — best in MLB.

The Cubs are 27-6 (.818) when they’ve scored in the first inning this season — best in MLB.

Mariners Hitting Stats & Trends

The Mariners are just 11-15 (.423) against the run line (-34.2% ROI) when underdogs this season — 2nd lowest in MLB.

The Mariners are just 19-34 (.358) against the run line (-17.8% ROI) vs bottom 10 scoring offenses this season Today, they face the Cubs (second in runs scored).

The Mariners are just 48-80 (.375) against the run line (-18.4% ROI) this season — lowest in MLB.

The Mariners are just 1-58 (.017) when trailing entering the 8th inning this season — tied for lowest in MLB.

Cubs Pitching Stats & Trends

Cubs pitchers have walked 11 of 55 batters (20%) when facing the leadoff batter in the inning over the past seven days (6 games) — highest in MLB; League Avg: 9%.

Cubs pitchers have walked 18 of 107 batters (17%) when facing the leadoff batter in the inning over the last 14 days (12 games) — highest in MLB; League Avg: 8%.

Cubs pitchers have walked 19 of 163 batters (12%) when facing the leadoff batter in the inning this month (18 games) — 3rd highest in MLB; League Avg: 8%.

Opponents have a groundball rate of 46% against Cubs pitchers over the past seven days (6 games) — 5th highest in MLB; League Avg: 42%.

Mariners Pitching Stats & Trends

Mariners pitchers have an ERA of 7.86 (52.2 IP) over the past seven days (6 games) — highest in MLB; League Avg: 4.19.

The Mariners have allowed 6.17 runs per game (74/12) over the last 14 days (12 games) — 2nd highest in MLB; League Avg: 4.35.

Mariners pitchers allowed an OBP of just .251 (1,441 PA’s) when facing the leadoff batter in the inning in the 2024 season — best in MLB; League Avg: .305.

Mariners pitchers have walked 10 of 150 batters (7%) when facing the leadoff batter in the inning this month (17 games) — tied for 4th best in MLB; League Avg: 8%.

More MLB Reading:

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

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