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

Odds updated as of 2:12 a.m.

On Tuesday in MLB, the Seattle Mariners are playing the Kansas City Royals.

Before checking out the MLB betting lines on FanDuel Sportsbook, we've got you covered, in terms of the most important information about this game.

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 (+116) | KC: +1.5 (-140)
• 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. When Gilbert starts, his team is 7-14-0 against the spread this season. When Gilbert starts a game and his team is the favorite on the moneyline, they have a record of 12-5. When Wacha starts, the Royals have gone 12-16-0 against the spread. The Royals have an 8-9 record in Wacha's 17 starts this season when they were the underdog on the moneyline.

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

• Looking at the moneyline for Royals-Mariners, Kansas City is the underdog at +116, and Seattle is -136 playing on the road.

Mariners vs Royals Spread

• The Royals are +1.5 on the run line against the Mariners. The Royals are -140 to cover, and the Mariners are +116.

Mariners vs Royals Over/Under

• Mariners versus Royals, on Sept. 16, has an over/under of 8.5, with the over being -105 and the under -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 season Seattle has been victorious 38 times in 58 chances when named as a favorite of at least -136 on the moneyline.
• Contests with the Mariners have gone over the total set by bookmakers in 78 of 145 chances this season.
• The Mariners have posted a record of 63-82-0 against the spread this season.
• The Royals have a 39-47 record in games they were listed as the moneyline underdog (winning 45.3% of those games).
• When it has played as a moneyline underdog with odds of +116 or longer, Kansas City has a 19-22 record (winning 46.3% of its games).
• 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 are 72-76-0 ATS this season.

Mariners Player Leaders

• Cal Raleigh has 134 hits and an OBP of .359, both of which are best among Seattle hitters this season. He has a .244 batting average and a slugging percentage of .577.
• He is 100th in batting average, 19th in on-base percentage, and third in slugging among qualified hitters in MLB.
• Raleigh will look for his fourth straight game with a hit in this contest. During his last five outings he is batting .375 with two doubles, a home run, eight walks and two RBIs.
• Julio Rodriguez leads Seattle in slugging percentage (.478) thanks to 64 extra-base hits. He's batting .269 with an on-base percentage of .321.
• He is 41st in batting average, 93rd in on-base percentage and 32nd in slugging among qualifying hitters.
• Rodriguez takes a five-game streak with at least one hit into this matchup. During his last five outings he is batting .400 with five doubles, three walks and four RBIs.
• Josh Naylor has 144 hits this season and has a slash line of .284/.344/.450.
• Naylor takes a two-game hitting streak into this game. In his last five games he is hitting .318 with a home run, a walk and six RBIs.
• Eugenio Suarez has been key for Seattle with 122 hits, an OBP of .300 plus a slugging percentage of .522.

Royals Player Leaders

• Bobby Witt Jr. has accumulated a slugging percentage of .501 and has 166 hits, both team-high figures for the Royals. He's batting .292 and with an on-base percentage of .350.
• Including all qualifying players in the majors, his batting average places him 13th, his on-base percentage ranks 37th, and he is 16th in slugging.
• Maikel Garcia leads his team with a .357 OBP. He has a batting average of .293 while slugging .464.
• His batting average is 12th among all qualified players, his on-base percentage is 22nd, and he is 42nd in slugging.
• Vinnie Pasquantino has 27 doubles, a triple, 30 home runs and 45 walks while hitting .265.
• Salvador Perez is hitting .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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