Kansas City Royals at Seattle Mariners, MLB forecast
Win probability
Starts from the pregame forecast, then moves with the score and the time left after each inning. Above the line favors SEA.
Game center
From the ESPN box score.
Top performers
Royals- Bobby Witt Jr.Batting1-4, 2 RBI
- Michael WachaPitching5.0 IP, 5 ER, 1 K
Mariners- Randy ArozarenaBatting2-4, 2 HR, 4 RBI
- George KirbyPitching6.0 IP, 1 ER, 5 K
Scoring summary
- 8Witt Jr. grounded into fielder's choice to shortstop, Rave scored, India out at second, Isbel to third.2–6
- 7Raleigh homered to center (393 feet).1–6
- 5Arozarena homered to center (401 feet), Crawford scored and Rodríguez scored.1–5
- 5Raleigh hit sacrifice fly to right, Young scored, Crawford to third.1–2
- 4Arozarena homered to right center (395 feet).1–1
- 3Witt Jr. singled to center, Isbel scored, India to third.1–0
The pick
Reconstructed from what was known before the game: the ratings at that point and the closing line.
Mariners 59%
Forecast Elo ratings alone
How often that comes true: MLB favorites the forecast gave 55–60% have won 55.5% of 2,596 graded games.
- Market
- SEA 59%
- ML KC +135 / SEA -160
- Pre-line forecast
- SEA 59%
- Elo + market-implied
- Elo ratings
- SEA 56%
- Ratings vs. market
- −3.2 pts
- SEA: Elo 55.9%, market 59.1%
- Fair odds
- SEA -145
- KC +145 · the forecast as odds, no margin
- Pregame projection
- KC 3.3 – 4.2 SEA
- Margin from the forecast, posted total 7.5
How the number is built
Elo inputs in rating points (higher favors that team; 25–28 Elo is about a point of spread in football and basketball), then how the pieces combine.
| Factor | KC | SEA | Why |
|---|---|---|---|
| Team rating | 1486 | 1513 | Elo entering the game; 1500 is league average |
| Home field | — | +18 | Worth 18 Elo in MLB |
| Starting pitchers | +5 | +1 | KC: Michael Wacha: team allows 0.23 fewer runs than with its usual starter (≈10 weighted starts) · SEA: George Kirby: team allows 0.03 fewer runs than with its usual starter (≈10 weighted starts) |
| Elo ratings | SEA +41 Elo | SEA 55.9% | |
| Market-implied ratings | SEA 59.7% | Team strength as past closing lines priced it, same game context | |
| Pre-line forecast | SEA 59.1% | 15% Elo, 85% market-implied (log-odds blend) | |
| Forecast | SEA 59.1% | Follows the market (vig removed): in testing, adding the ratings made it less accurate | |
Tale of the tape
This season coming into the game, regular season, each number with its league rank (the longer the bar, the higher). Home and road: the host's record at home against the visitor's on the road. Opponent Elo: how strong the teams each has played are, 1st the toughest.
| KC | Stat | SEA |
|---|---|---|
| 30th of 303.3 | Runs scored | 4.612th of 30 |
| 3rd of 303.7 | Runs allowed | 4.420th of 30 |
| 21st of 30−0.4 | Margin | +0.214th of 30 |
| 25th of 303–7 | Last 10 | 6–45th of 30 |
| 17th of 3019–21 | Road vs home | 20–1920th of 30 |
| 13th of 301501 | Opponent Elo | 149428th of 30 |
| 23rd of 301486 | Elo rating | 151313th of 30 |
Rating history
Each team's Elo over the last two seasons. Hover or drag to compare on any date.
Recent form
Last five results, and whether the forecast hit.
Against the line
How each team has done against the closing spread and total, coming into this game.
| This season |  KC |  SEA |
|---|---|---|
| Run line | 40–44 | 36–47 |
| Last 10 | 5–5 | 6–4 |
| Favorite | 10–27 | 14–34 |
| Underdog | 30–17 | 22–13 |
| Overs–unders | 33–51 | 47–36 |
| Overs–unders, last 10 | 2–8 | 8–2 |
Against each game's closing line. Books set every line knowing these records: across 3,901 past games, the team with the better record against the spread so far that season covered 51.2%, short of the 52.4% a standard −110 bet needs, and over/under streaks held 48.0% of the time. They describe the past.
Head to head
KC 4–9 SEA in their last 13 meetings; the forecast called 8 of 13.