• The Reds are -110 favorites vs the Mariners
• Reds vs Mariners Over / Under today: 7.5 Runs
• Reds / Mariners TV Channel: MRTV | RDTV

The Cincinnati Reds (-110) visit T-Mobile Park to take on the Seattle Mariners (-110) on July 21, 2026. First pitch is scheduled for 9:40 pm in Seattle, WA.

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

Reds vs Mariners Starting Pitchers Today:

• Reds starting pitcher: Chase Burns 11-1, 2.54 ERA
• Mariners starting pitcher: Luis Castillo 3-8, 4.95 ERA

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

Reds vs Mariners Prediction for Today’s Game

Based on recent trends the model predicts the Mariners will win Tuesday‘s MLB game with 52.8% confidence, factoring in game simulations, recent player performances, starting pitchers and injuries.

Bet now on Reds vs Mariners and all games with BetMGM

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

Best Reds Player Prop Bets Today:

• Ke’Bryan Hayes has hit the Hits Runs and RBIs Under in 18 of his last 25 away games (+12.30 Units / 38% ROI)
• Sal Stewart has hit the Home Runs Over in 4 of his last 10 away games (+10.25 Units / 102% ROI)
• JJ Bleday has hit the Singles Over in 13 of his last 20 games (+10.15 Units / 50% ROI)
• Ke’Bryan Hayes has hit the Hits Under in 16 of his last 25 away games (+9.35 Units / 37% ROI)
• JJ Bleday has hit the Walks Over in 12 of his last 20 games (+9.15 Units / 46% ROI)

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

Best Mariners Player Prop Best Bets Today:

• Cole Young has hit the Home Runs Over in 4 of his last 10 games (+25.00 Units / 250% ROI)
• Luke Raley has hit the Runs Under in 22 of his last 25 games (+17.55 Units / 38% ROI)
• J.P. Crawford has hit the Hits Runs and RBIs Under in 21 of his last 25 games at home (+15.80 Units / 48% ROI)
• Cal Raleigh has hit the Total Bases Under in 16 of his last 20 games at home (+12.20 Units / 48% ROI)
• J.P. Crawford has hit the Hits Under in 15 of his last 25 games at home (+10.75 Units / 43% ROI)

Reds Best Bets Today:

• The Cincinnati Reds have hit the Team Total Under in 30 of their last 45 games (+13.50 Units / 26% ROI)
• The Cincinnati Reds have hit the Game Total Over in 29 of their last 45 away games (+11.35 Units / 23% ROI)
• The Cincinnati Reds have hit the 1st Five Innings (F5) Team Total Over in 22 of their last 35 away games (+7.85 Units / 18% ROI)
• The Cincinnati Reds have covered the 1st Five Innings (F5) Run Line in 22 of their last 35 games (+7.65 Units / 19% ROI)
• The Cincinnati Reds have hit the 1st Five Innings (F5) Moneyline in 13 of their last 30 away games (+4.85 Units / 14% ROI)

Mariners Best Bets Today:

• The Seattle Mariners have hit the Team Total Under in 20 of their last 30 games (+9.65 Units / 28% ROI)
• The Seattle Mariners have hit the Moneyline in 17 of their last 23 games at home (+9.05 Units / 26% ROI)
• The Seattle Mariners have hit the 1st Five Innings (F5) Team Total Under in 20 of their last 30 games (+8.95 Units / 24% ROI)
• The Seattle Mariners have hit the Game Total Over in 22 of their last 40 games (+6.75 Units / 15% ROI)
• The Seattle Mariners have covered the Run Line in 10 of their last 18 games at home (+5.10 Units / 27% ROI)

Reds Against the Spread (ATS) Record

Against the spread this season, the Reds 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

Mariners Against the Spread (ATS) Record

Against the spread this season, the Mariners 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

Mariners vs Reds Home Run Prop Bets Today

Mariners vs Reds Total Hits Prop Bets Today

Mariners vs Reds Strikeout Prop Bets Today

Reds Keys to the Game vs. the Mariners

The Reds are just 3-15 (.167) when tied entering the 7th inning this season — lowest in MLB; League Avg: .500.

The Reds are just 8-43 (.157) when allowing 5 or more runs this season — 5th lowest in MLB; League Avg: .207.

The Reds are 5-47 (.096) when trailing entering the 9th inning this season — 2nd best in MLB; League Avg: .053.

The Reds are just 5-28 (.152) when allowing 10 or more hits this season — 4th lowest in MLB; League Avg: .248.

Mariners Keys to the Game vs. the Reds

The Mariners are just 1-40 (.024) when trailing entering the 8th inning this season — 3rd lowest in MLB; League Avg: .098.

The Mariners are just 15-26 (.366) vs bottom 10 scoring offenses this season Today, they face the Reds (21st in runs scored).

The Mariners are just 1-44 (.022) when trailing entering the 9th inning this season — 3rd lowest in MLB; League Avg: .053.

The Mariners are just 6-35 (.146) when allowing 5 or more runs this season — 4th lowest in MLB; League Avg: .207.

Reds Hitting Stats & Trends

The Reds are batting just .213 with two outs this season — lowest in MLB.

The Reds are batting just .118 on pitches out of the zone this season — lowest in MLB.

Reds hitters have an OPS of .767 (911 PA’s) against LHP this season — 5th best in MLB.

Reds hitters are slugging just .170 on pitches out of the zone this season — lowest in MLB.

Mariners Hitting Stats & Trends

The Mariners are batting just .215 against LHP this season — tied for lowest in MLB.

Mariners hitters are slugging just .334 against LHP this season — lowest in MLB.

Mariners hitters have 53 extra-base hits out of 202 total hits (just 26%) against LHP this season — lowest in MLB.

Mariners hitters have an OPS of just .633 (1,072 PA’s) against LHP this season — lowest in MLB.

Reds Pitching Stats & Trends

Reds pitchers have walked 11% of batters this season — 2nd highest in MLB.

Reds pitchers have a first-pitch strike rate of just 58% this season — lowest in MLB.

Reds pitchers have an ERA of 5.60 (244.1 IP) against division opponents this season — 2nd highest in MLB.

Reds pitchers have a strike rate of just 62% this season — tied for lowest in MLB.

Mariners Pitching Stats & Trends

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

Mariners pitchers have walked 6% of batters when facing the leadoff batter in the inning this season — 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.

More MLB Reading:

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

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