Royals vs Mariners Prediction, Odds, Moneyline, Spread & Over/Under for Sept. 17

Odds updated as of 7:16 p.m.

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

All the info you need to make smart wagers on this game at FanDuel Sportsbook can be found below. Check out all of the latest MLB betting lines here.

Royals vs Mariners Game Info

• Kansas City Royals (75-76) vs. Seattle Mariners (83-68)
• Date: Wednesday, September 17, 2025
• Time: 7:40 p.m. ET
• Venue: Kauffman Stadium -- Kansas City, Missouri
• Coverage: FDSKC and ROOT Sports NW

Royals vs Mariners Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: KC: (-124) | SEA: (+106)
• Spread: KC: -1.5 (+162) | SEA: +1.5 (-196)
• Total: 8.5 -- Over: (-120) | Under: (-102)

Royals vs Mariners Probable Starting Pitchers

Probable Pitchers: Cole Ragans (Royals) - 2-3, 5.18 ERA vs Bryce Miller (Mariners) - 4-5, 5.59 ERA

The probable starters are Cole Ragans (2-3) for the Royals and Bryce Miller (4-5) for the Mariners. Ragans' team is 4-6-0 against the spread this season in his starts. When Ragans starts a game and his team is the favorite on the moneyline, they have a record of 4-4. The Mariners have a 7-8-0 ATS record in Miller's 15 starts with a set spread. The Mariners have a 2-3 record in Miller's five starts this season when they were the underdog on the moneyline.

Royals vs Mariners Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Royals win (53.6%)

Royals vs Mariners Moneyline

• Kansas City is the favorite, -124 on the moneyline, while Seattle is a +106 underdog on the road.

Royals vs Mariners Spread

• The Royals are hosting the Mariners and are favored by 1.5 runs (+162 to cover) on the runline. Seattle is -196 to cover.

Royals vs Mariners Over/Under

• Royals versus Mariners, on Sept. 17, has an over/under of 8.5, with the over being -120 and the under -102.

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

Royals vs Mariners Betting Trends

• The Royals have been victorious in 35, or 56.5%, of the 62 contests they have been chosen as favorites in this season.
• This season Kansas City has come away with a win 23 times in 40 chances when named as a favorite of at least -124 on the moneyline.
• The Royals and their opponents have hit the over in 64 of their 149 games with a total set by oddsmakers this season.
• The Royals are 72-77-0 against the spread in their 149 games with a line set by sportsbooks this season.
• The Mariners have been the underdog on the moneyline 38 total times this season. They've gone 18-20 in those games.
• When it has played as a moneyline underdog with odds of +106 or longer, Seattle has a 13-11 record (winning 54.2% of its games).
• The Mariners have combined with opponents to hit the over on the total 79 times this season for a 79-62-5 record against the over/under.
• The Mariners have collected a 64-82-0 record ATS this season (covering 43.8% of the time).

Royals Player Leaders

• Bobby Witt Jr. has 167 hits to go with a slugging percentage of .500, both of which lead Kansas City hitters this season. He has a .292 batting average and an on-base percentage of .352.
• Among all qualifying hitters in baseball, he ranks 12th in batting average, 35th in on-base percentage, and 18th in slugging.
• Witt has picked up at least one hit in two games in a row. During his last five outings he is hitting .211 with a triple, a home run, two walks and two RBIs.
• Maikel Garcia leads Kansas City in OBP (.354) this season, fueled by 160 hits. He's batting .289 while slugging .458.
• His batting average is 15th among qualified players, his on-base percentage 32nd, and his slugging percentage 51st.
• Vinnie Pasquantino has 151 hits this season and has a slash line of .263/.321/.470.
• Salvador Perez is batting .237 with a .277 OBP and 89 RBI for Kansas City this season.
• Perez takes a three-game hitting streak into this game. In his last five games he is hitting .273 with three home runs and eight RBIs.

Mariners Player Leaders

• Cal Raleigh has put up an on-base percentage of .361 and has 137 hits, both team-best figures for the Mariners. He's batting .247 and slugging .590.
• He is 99th in batting average, 17th in on-base percentage and third in slugging percentage among all qualified hitters in the big leagues.
• Raleigh hopes to build on a four-game hitting streak in this matchup. In his last five games he is batting .444 with three doubles, three home runs, five walks and five RBIs.
• Julio Rodriguez's .480 slugging percentage leads his team. He has a batting average of .271 with an on-base percentage of .323.
• His batting average ranks 37th among all qualified players, his on-base percentage ranks 87th, and he is 31st in slugging.
• Josh Naylor has 26 doubles, a triple, 19 home runs and 46 walks while hitting .283.
• Eugenio Suarez has 25 doubles, 45 home runs and 44 walks while batting .224.

Royals vs Mariners Head to Head

• 9/16/2025: 12-5 SEA (Favorite: Mariners, Spread: -1.5, Total: 8.5, Favorite Moneyline: -136, Underdog Moneyline: +116)
• 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)

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