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

Odds updated as of 4:17 a.m.

Wednesday's slate in the MLB includes a matchup between the Kansas City Royals and the Seattle Mariners.

All the information you need to make smart bets on this matchup 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: (-112) | SEA: (-104)
• Spread: KC: +1.5 (-188) | SEA: -1.5 (+155)
• Total: 8.5 -- Over: (-110) | Under: (-110)

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

Royals vs Mariners Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Mariners win (51%)

Royals vs Mariners Moneyline

• Seattle is the underdog, -104 on the moneyline, while Kansas City is a -112 favorite at home.

Royals vs Mariners Spread

• The Mariners are 1.5-run favorites against the spread for this matchup with the Royals. The Mariners are +155 to cover, while the Royals are -188 to cover as a 1.5-run underdog on the runline.

Royals vs Mariners Over/Under

• A total of 8.5 runs has been set for the Royals-Mariners game on Sept. 17, with the over available at -110 and the under at -110.

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

Royals vs Mariners Betting Trends

• The Royals have been favorites in 62 games this season and have come away with the win 35 times (56.5%) in those contests.
• This season Kansas City has been victorious 35 times in 62 chances when named as a favorite of at least -112 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 that had a posted line this season.
• The Mariners have won 47.4% of the games this season they were the moneyline underdog (18-20).
• Seattle has an 18-17 record (winning 51.4% of its games) when it has played as a moneyline underdog of -104 or longer.
• The Mariners have played in 146 games with a set over/under, and have combined with opponents to go over the total 79 times (79-62-5).
• The Mariners have collected a 64-82-0 record against the spread this season (covering 43.8% of the time).

Royals Player Leaders

• Bobby Witt Jr. leads Kansas City with 167 hits and a team-best slugging percentage of .500. He's batting .292 with an on-base percentage of .352.
• Among qualifying hitters in the majors, his batting average ranks 12th, his on-base percentage ranks 34th, and he is 18th in slugging.
• Witt will look for his third straight game with a hit in this contest. In his last five games 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.
• Among qualifying batters, his batting average places him 15th, his on-base percentage 32nd, and his slugging percentage 51st.
• Vinnie Pasquantino has collected 151 base hits, an OBP of .321 and a slugging percentage of .470 this season.
• Salvador Perez has been key for Kansas City with 132 hits, an OBP of .277 plus a slugging percentage of .448.
• Perez heads into this game on a three-game hitting streak. In his last five games he is batting .273 with three home runs and eight RBIs.

Mariners Player Leaders

• Cal Raleigh has racked up an on-base percentage of .361 and has 137 hits, both team-best marks for the Mariners. He's batting .247 and slugging .590.
• Including all qualifying hitters in MLB, he is 100th in batting average, 17th in on-base percentage and third in slugging percentage.
• Raleigh hopes to build on a four-game hitting streak in this matchup. During his last five outings he is hitting .444 with three doubles, three home runs, five walks and five RBIs.
• Julio Rodriguez is slugging .480 to lead his team. He has a batting average of .271 with an on-base percentage of .323.
• Including all qualifying hitters, he ranks 37th in batting average, 87th in on-base percentage and 31st in slugging percentage.
• Josh Naylor is batting .283 with 26 doubles, a triple, 19 home runs and 46 walks.
• Eugenio Suarez is batting .224 with 25 doubles, 45 home runs and 44 walks.

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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