Mariners vs Royals Prediction, Odds, Moneyline, Spread & Over/Under for Sept. 16

Odds updated as of 4:17 a.m.

The Seattle Mariners versus the Kansas City Royals is on the MLB schedule for Tuesday.

Before you do any MLB betting on this matchup at FanDuel Sportsbook, here's what you need to know.

Mariners vs Royals Game Info

• Seattle Mariners (82-68) vs. Kansas City Royals (75-75)
• Date: Tuesday, September 16, 2025
• Time: 7:40 p.m. ET
• Venue: Kauffman Stadium -- Kansas City, Missouri
• Coverage: FDSKC and ROOT Sports NW

Mariners vs Royals Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-136) | KC: (+116)
• Spread: SEA: -1.5 (+118) | KC: +1.5 (-142)
• Total: 8.5 -- Over: (-105) | Under: (-115)

Mariners vs Royals Probable Starting Pitchers

Probable Pitchers: Logan Gilbert (Mariners) - 4-6, 3.54 ERA vs Michael Wacha (Royals) - 9-11, 3.45 ERA

The probable starters are Logan Gilbert (4-6) for the Mariners and Michael Wacha (9-11) for the Royals. Gilbert's team is 7-14-0 against the spread in his starts this season. Gilbert's team is 12-5 this season when he starts and they are the moneyline favorite. The Royals have gone 12-16-0 against the spread when Wacha starts. The Royals are 8-9 in Wacha's 17 starts this season that they were the moneyline underdog.

Mariners vs Royals Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Mariners win (56.9%)

Mariners vs Royals Moneyline

• The Mariners vs Royals moneyline has Seattle as a -136 favorite, while Kansas City is a +116 underdog at home.

Mariners vs Royals Spread

• The Royals are +1.5 on the spread (-142 to cover), and Seattle is +118 to cover the runline.

Mariners vs Royals Over/Under

• The Mariners-Royals contest on Sept. 16 has been given an over/under of 8.5 runs. The over is set at -105 and the under at -115.

Bet on Seattle Mariners vs. Kansas City Royals on FanDuel today!

Mariners vs Royals Betting Trends

• The Mariners have been victorious in 60, or 58.3%, of the 103 contests they have been chosen as favorites in this season.
• This year Seattle has won 38 of 58 games when listed as at least -136 on the moneyline.
• The Mariners' games have gone over the total in 78 of their 145 opportunities.
• The Mariners are 63-82-0 against the spread in their 145 games that had a posted line this season.
• The Royals have won 45.3% of the games this season they were the underdog on the moneyline (39-47).
• Kansas City has a 19-22 record (winning 46.3% of its games) when playing as a moneyline underdog of +116 or longer.
• The Royals have combined with opponents to hit the over on the total 63 times this season for a 63-83-2 record against the over/under.
• The Royals have collected a 72-76-0 record ATS this season (covering 48.6% of the time).

Mariners Player Leaders

• Cal Raleigh leads Seattle in OBP (.359) and total hits (134) this season. He's batting .244 batting average while slugging .577.
• Among all qualified hitters in MLB, he ranks 99th in batting average, 19th in on-base percentage, and third in slugging.
• Raleigh hopes to build on a three-game hitting streak in this matchup. During his last five outings he is batting .375 with two doubles, a home run, eight walks and two RBIs.
• Julio Rodriguez has hit 30 homers this season while driving in 91 runs. He's batting .269 this season and slugging .478 with an on-base percentage of .321.
• Among qualifying batters, his batting average ranks him 40th, his on-base percentage 93rd, and his slugging percentage 32nd.
• Rodriguez has picked up at least one hit in five games in a row. During his last five outings he is hitting .400 with five doubles, three walks and four RBIs.
• Josh Naylor is batting .284 with a .450 slugging percentage and 85 RBI this year.
• Naylor takes a two-game hitting streak into this game. During his last five outings he is hitting .318 with a home run, a walk and six RBIs.
• Eugenio Suarez has 45 home runs, 109 RBI and a batting average of .226 this season.

Royals Player Leaders

• Bobby Witt Jr. has 166 hits with a .501 slugging percentage, both team-best numbers for the Royals. He's batting .292 and with an on-base percentage of .350.
• Including all qualifying hitters in the big leagues, he ranks 13th in batting average, 37th in on-base percentage and 17th in slugging percentage.
• Maikel Garcia has a .357 on-base percentage to pace his team. He has a batting average of .293 while slugging .464.
• He is 12th in batting average, 23rd in on-base percentage and 43rd in slugging percentage in MLB.
• Vinnie Pasquantino is hitting .265 with 27 doubles, a triple, 30 home runs and 45 walks.
• Salvador Perez is batting .237 with 34 doubles, 28 home runs and 23 walks.

Mariners vs Royals Head to Head

• 7/3/2025: 3-2 KC (Favorite: Mariners, Spread: -1.5, Total: 7.5, Favorite Moneyline: -120, Underdog Moneyline: +102)
• 7/2/2025: 3-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -166, Underdog Moneyline: +140)
• 7/1/2025: 6-3 KC (Favorite: Mariners, Spread: -1.5, Total: 8, Favorite Moneyline: -138, Underdog Moneyline: +118)
• 6/30/2025: 6-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -164, Underdog Moneyline: +138)
• 6/9/2024: 6-5 SEA (Favorite: Royals, Spread: -1.5, Total: 7.5, Favorite Moneyline: -136, Underdog Moneyline: +116)
• 6/8/2024: 8-4 KC (Favorite: Mariners, Spread: -1.5, Total: 8.5, Favorite Moneyline: -134, Underdog Moneyline: +114)
• 6/7/2024: 10-9 KC (Favorite: Mariners, Spread: -1.5, Total: 9, Favorite Moneyline: -122, Underdog Moneyline: +104)
• 5/15/2024: 4-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 8, Favorite Moneyline: -142, Underdog Moneyline: +120)
• 5/14/2024: 4-2 KC (Favorite: Mariners, Spread: -1.5, Total: 7.5, Favorite Moneyline: -164, Underdog Moneyline: +138)
• 5/13/2024: 6-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -154, Underdog Moneyline: +130)

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