Prediction Details

MLB Prediction: Seattle Mariners vs Kansas City Royals (Thursday, September 18 at 02:10 PM ET)

Introduction

Updated

SEA @ KCSEA -120KC +101O/U 9.0
Market / Trend SEA KC
Moneyline -120 +101
Total (O/U) 9.0
Run Line -1.5 (130) +1.5 (-152)
Last 5 RPG 7.0 6.0
Record 83–69 76–76
Lines: BetMGM, BetOnline.ag, BetRivers, BetUS +7 more

More MLB picks: Seattle Mariners · Kansas City Royals

Seattle Mariners’ surge is undeniable, winning 9 of their last 10 while averaging 7.3 runs per game, a scoring profile that immediately jumps off the page in this MLB prediction. Kansas City, meanwhile, has dropped 7 of its last 10 with just 3.9 runs per contest, underscoring the gap in offensive rhythm. With Seattle Mariners’ bats surging and Kansas City struggling to keep pace, this matchup tilts heavily toward the visitors and points to a higher-scoring outcome than the market expects.

Game Time

Starts in 3h 13m

Coverage starts at Thursday, September 18 at 02:10 PM ET at Kauffman Stadium, expansive gaps limit homers.

Odds & Spread Line

  • Seattle Mariners: -120
  • Kansas City Royals: +101

Total: 9

  • Run Line — Seattle Mariners: -1.5 (+130)
  • Run Line — Kansas City Royals: +1.5 (-152)

Latest Team Records

Seattle Mariners: 83-69 (Win %: 0.546)
Kansas City Royals: 76-76 (Win %: 0.5)

Injury Report

Both teams are currently healthy with no major injury concerns.

Key Player Stats

Seattle Mariners

  • Cal Raleigh: 0.247 AVG, 56 HR, 118 RBI
  • Eugenio Suarez: 0.23 AVG, 46 HR, 111 RBI
  • Julio Rodriguez: 0.271 AVG, 30 HR, 93 RBI

Kansas City Royals

  • Vinnie Pasquantino: 0.264 AVG, 30 HR, 104 RBI
  • Bobby Witt Jr.: 0.293 AVG, 22 HR, 80 RBI
  • Salvador Perez: 0.237 AVG, 29 HR, 92 RBI

Team Analysis

Seattle Mariners

Seattle Mariners’ 4-1 record across the last 5 games reflects a team firing on all cylinders, with 7.0 runs per game backing their surge. That offensive burst has been fueled by consistent production from Cal Raleigh and Eugenio Suarez, two bats capable of changing games with power. Even on the road, where their overall record sits below .500, the Mariners’ current form signals value against a Royals team trending downward.

Momentum becomes even clearer when looking at the last 10 games, where Seattle has gone 9-1 while putting up 7.3 runs per contest. Julio Rodriguez’s ability to drive in runs has complemented the power bats, giving the lineup balance and depth. With their offense clicking and confidence high, the Mariners have the profile of a team that can extend their winning rhythm into another strong performance here.

  • Batting Average: 0.245
  • Total Runs Scored: 722
  • Home Runs: 223
  • OBP: 0.321
  • SLG: 0.42
  • OPS: 0.741
  • ERA: 3.94
  • WHIP: 1.24

Away Record: 35-42 • Home Record: 48-27
Last 5 Games: 4-1 (7.0 RPG)
Last 10 Games: 9-1 (7.3 RPG)


Kansas City Royals

Kansas City has stumbled to a 2-3 mark in its last 5 games, scoring 6.0 runs per contest but still failing to convert offense into consistent wins. Bobby Witt Jr. has been a steady contributor, yet the team’s inability to string together victories at home has capped their upside. That inconsistency looms large against an opponent thriving with momentum.

Across the last 10 outings, the Royals are just 3-7 while averaging 3.9 runs, a pace that simply doesn’t keep up with Seattle Mariners’ current production. Vinnie Pasquantino’s contributions have provided some spark, but the supporting cast has not matched the Mariners’ relentless scoring. Even with Salvador Perez adding veteran stability, Kansas City Royals’ recent rhythm suggests they will struggle to match runs in this spot.

  • Batting Average: 0.245
  • Total Runs Scored: 589
  • Home Runs: 148
  • OBP: 0.306
  • SLG: 0.393
  • OPS: 0.699
  • ERA: 3.79
  • WHIP: 1.26

Away Record: 35-40 • Home Record: 41-36
Last 5 Games: 2-3 (6.0 RPG)
Last 10 Games: 3-7 (3.9 RPG)


Head-to-Head History

Tied 3–3 (Last 6 games)

  • September 17, 2025: SEA 5 @ KC 7
  • September 16, 2025: SEA 12 @ KC 5
  • July 03, 2025: KC 3 @ SEA 2
  • July 02, 2025: KC 2 @ SEA 3
  • July 01, 2025: KC 6 @ SEA 3
  • June 30, 2025: KC 2 @ SEA 6

Over/Under Trends

Seattle Mariners’ last 10 games have averaged 10.6 total runs, with 5 games that would have cleared today’s total of 9.

Kansas City Royals’ last 10 games have averaged 9.8 combined runs, with 6 games clearing the same number of 9.

Moneyline Betting Prediction

Seattle Mariners’ recent 9-1 run paired with elite scoring output gives them a decisive edge over a Kansas City side that has dropped 7 of its last 10 and struggled to sustain offense. With Cal Raleigh and Julio Rodriguez anchoring a lineup that continues to produce runs at a high rate, the Mariners project as the superior team and the clear moneyline play.

Data supports the Seattle Mariners as the right side.

Over/Under Prediction

Last five form shows the Kansas City Royals at 6.0 RPG and the Seattle Mariners at 7.0, giving context for the number.

These teams are combining for 13.0 runs per game recently — above the posted total of 9.0. That points toward the Over 9.0.

Bookmakers

You’ll find these markets at: FanDuel, MyBookie.ag, Fanatics, LowVig.ag, BetOnline.ag, Caesars, DraftKings, BetMGM, BetUS, BetRivers, Bovada.

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MLB Predictions FAQ

How should I size my bets?

Use a consistent unit (about 1–2% of bankroll). Singles should be most of your volume. We like parlays—smart ones. Keep legs tight (2–3), cap risk to 0.25–0.5u, and pass when the price isn’t there.

What do moneyline, run line, and total mean?

Moneyline is who wins the game. Run line is a spread, usually ±1.5 runs. The total (over/under) is combined runs by both teams.

What’s a good price range for today’s pick (Sep 18, 2025)?

We list a target price in the post. If the market moves past that number, reduce stake size or pass instead of chasing worse odds.

John Tamburino

John TamburinoVerified

Lead Analyst — data-first, former college baseball.

John Tamburino grew up on travel baseball and three years of varsity basketball, then played college baseball before shifting to analytics. He still watches everything—from weekday tennis to all major league sports—and will never forget the Diamondbacks’ World Series run. At Parlamaz, John blends trusted data feeds with matchup context to find real value—no fluff, no paywalls.