• The Royals are +105 favorites vs the Mariners
• Royals vs Mariners Over / Under today: 8 Runs
• Royals / Mariners TV Channel: RYTV | MRTV

The Kansas City Royals (+105) visit T-Mobile Park to take on the Seattle Mariners (-125) on May 3, 2026. First pitch is scheduled for 4:10 pm in Seattle, WA.

This season, the Royals are 14-19 against the spread (ATS), while the Mariners are 12-22 ATS.

Royals vs Mariners Starting Pitchers Today:

• Royals starting pitcher: Kris Bubic 2-1, 3.78 ERA
• Mariners starting pitcher: Luis Castillo 0-2, 6.51 ERA

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

Royals vs Mariners Prediction for Today’s Game

Based on recent trends the model predicts the Mariners will win Sunday‘s MLB game with 52.0% confidence, factoring in game simulations, recent player performances, starting pitchers and injuries.

Bet now on Royals vs Mariners and all games with BetMGM

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

Best Royals Player Prop Bets Today:

• Vinnie Pasquantino has hit the Home Runs Over in 3 of his last 7 away games (+12.00 Units / 171% ROI)
• Vinnie Pasquantino has hit the Singles Under in 16 of his last 20 games (+10.20 Units / 39% ROI)
• Isaac Collins has hit the Runs Under in his last 10 away games (+10.00 Units / 44% ROI)
• Salvador Perez has hit the Hits Runs and RBIs Under in 17 of his last 25 games (+8.60 Units / 30% ROI)
• Vinnie Pasquantino has hit the Hits Under in 11 of his last 20 games (+7.95 Units / 37% ROI)

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

Best Mariners Player Prop Best Bets Today:

• Julio Rodriguez has hit the Hits Over in his last 10 games at home (+10.90 Units / 53% ROI)
• Cole Young has hit the Singles Over in 11 of his last 15 games (+10.50 Units / 70% ROI)
• Cole Young has hit the Walks Under in his last 10 games (+10.00 Units / 43% ROI)
• Cal Raleigh has hit the Home Runs Over in 5 of his last 10 games (+9.80 Units / 98% ROI)
• Josh Naylor has hit the Runs Under in 19 of his last 25 games (+9.05 Units / 21% ROI)

Royals Best Bets Today:

• The Kansas City Royals have hit the 1st Five Innings (F5) Team Total Under in 14 of their last 17 away games (+10.95 Units / 56% ROI)
• The Kansas City Royals have hit the Game Total Under in 15 of their last 20 away games (+9.45 Units / 43% ROI)
• The Kansas City Royals have hit the Team Total Under in 14 of their last 20 away games (+6.95 Units / 30% ROI)
• The Kansas City Royals have hit the Moneyline in 6 of their last 8 games (+4.35 Units / 50% ROI)
• The Kansas City Royals have covered the Run Line in 6 of their last 8 games (+3.65 Units / 31% ROI)

Mariners Best Bets Today:

• The Seattle Mariners have hit the 1st Five Innings (F5) Moneyline in 29 of their last 50 games at home (+9.85 Units / 11% ROI)
• The Seattle Mariners have hit the Moneyline in 33 of their last 50 games at home (+9.20 Units / 11% ROI)
• The Seattle Mariners have hit the Team Total Over in 30 of their last 50 games at home (+7.85 Units / 13% ROI)
• The Seattle Mariners have hit the 1st Five Innings (F5) Team Total Over in 30 of their last 50 games at home (+6.90 Units / 11% ROI)
• The Seattle Mariners have hit the Game Total Over in 14 of their last 22 games at home (+5.25 Units / 22% ROI)

Royals Against the Spread (ATS) Record

Against the spread this season, the Royals are 15-17 against the Run Line (-6.1 Units / -13.2% ROI).

• 14-19 when betting on the Moneyline for -7.55 Units / -18.99% ROI
• 14-19 when betting on the total runs Over for -6.75 Units / -18.54% ROI
• 19-14 when betting on the total runs Under for +3.85 Units / 10.64% ROI

Mariners Against the Spread (ATS) Record

Against the spread this season, the Mariners are 12-22 against the Run Line (-7.75 Units / -21.44% ROI).

• 16-18 when betting on the Moneyline for -8.3 Units / -17.26% ROI
• 16-17 when betting on the total runs Over for -2.6 Units / -6.94% ROI
• 17-16 when betting on the total runs Under for -0.45 Units / -1.2% ROI

Mariners vs Royals Home Run Prop Bets Today

Mariners vs Royals Total Hits Prop Bets Today

Mariners vs Royals Strikeout Prop Bets Today

Royals Keys to the Game vs. the Mariners

The Royals are just 10-4 (.714) when leading entering the 8th inning this season — lowest in MLB; League Avg: .888.

The Royals are just 1-9 (.100) when allowing 10 or more hits this season — 3rd lowest in MLB; League Avg: .240.

The Royals are just 5-12 (.294) on the road this season — 2nd lowest in MLB; League Avg: .468.

The Royals are 69-7 (.908) when leading entering the 7th inning since the 2025 season — 5th best in MLB; League Avg: .871.

Mariners Keys to the Game vs. the Royals

The Mariners are just 2-8 (.200) vs bottom 10 scoring offenses this season Today, they face the Royals (23rd in runs scored).

The Mariners are 14-68 (.171) when trailing entering the 7th inning since the 2025 season — 5th best in MLB; League Avg: .128.

The Mariners are 10-69 (.127) when trailing entering the 8th inning since the 2025 season — 3rd best in MLB; League Avg: .094.

The Mariners are 80-5 (.941) when leading entering the 8th inning since the 2025 season — 4th best in MLB; League Avg: .906.

Royals Hitting Stats & Trends

Royals hitters have struck out in just 18% of their PA’s against RHP since the 2025 season — 2nd best in MLB.

34% of Royals hitters strikeouts have come on 95+ MPH fastballs this season — highest in MLB.

Royals hitters have struck out in just 19% of their PA’s since the 2025 season — 2nd best in MLB.

Royals hitters have an OPS of 1.352 (236 PA’s) with the pitcher behind in the count this season — best in MLB.

Mariners Hitting Stats & Trends

Mariners hitters are slugging .678 on the first pitch of at-bats since the 2025 season — 2nd best in MLB.

Mariners hitters have put just 31% of their swings in play with runners in scoring position this season — lowest in MLB.

The Mariners are batting just .203 against LHP this season — 3rd lowest in MLB.

The Mariners batted just .207 when facing the starting pitcher for the 3rd time in a game in the 2024 season — lowest in MLB; League Avg: .263.

Royals Pitching Stats & Trends

Opponents have a groundball rate of just 38% against Royals pitchers this season — lowest in MLB.

Royals pitchers have walked 12% of batters this season — 5th highest in MLB.

Opponents have a groundball rate of just 34% against Royals pitchers over the past seven days (6 games) — 3rd lowest in MLB.

Royals pitchers have 60 three-pitch strikeouts this season — 5th most in MLB.

Mariners Pitching Stats & Trends

Mariners pitchers have a first-pitch strike rate of 68% this season — highest in MLB.

Mariners pitchers have thrown at least two strikes in their first three pitches to 71% of opposing batters this season — highest in MLB.

Mariners pitchers have walked 7% of batters since the 2025 season — 2nd best in MLB.

Mariners pitchers have induced opposing hitters to ground into 33 double plays in 237 opportunities (14%) this season — best in MLB.

More MLB Reading:

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

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