Boston Red Sox at Kansas City Royals, 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 KC.
Game center
From the ESPN box score.
Top performers
Red Sox- Jarren DuranBatting2-5, 1 HR, 2 RBI
- Connelly EarlyPitching6.1 IP, 3 ER, 5 K
Royals- Salvador PerezBatting3-4, 1 HR, 1 RBI
- Michael WachaPitching6.0 IP, 1 ER, 8 K
Scoring summary
- 7Duran homered to left (366 feet), Narváez scored.4–3
- 5Díaz homered to left center (405 feet), Marte scored.2–3
- 2Narváez grounded into double play, third to first, Rafaela scored, Mayer to second, Sogard out at third.2–1
- 2Sogard singled to right, Contreras scored, Rafaela to third.1–1
- 1Perez homered to left (379 feet).0–1
The pick
Reconstructed from what was known before the game: the ratings at that point and the closing line.
Royals 51%
Forecast Elo ratings alone
How often that comes true: MLB favorites the forecast gave 50–55% have won 52.7% of 2,871 graded games.
- Market
- KC 51%
- ML BOS -105 / KC -114
- Pre-line forecast
- KC 50%
- Elo + market-implied
- Elo ratings
- KC 48%
- Ratings vs. market
- −2.9 pts
- KC: Elo 48.1%, market 51.0%
- Fair odds
- KC -104
- BOS +104 · the forecast as odds, no margin
- Pregame projection
- BOS 3.7 – 3.8 KC
- 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 | BOS | KC | Why |
|---|---|---|---|
| Team rating | 1512 | 1488 | Elo entering the game; 1500 is league average |
| Home field | — | +18 | Worth 18 Elo in MLB |
| Starting pitchers | +10 | +3 | BOS: Connelly Early: team allows 0.48 fewer runs than with its usual starter (≈8 weighted starts) · KC: Michael Wacha: team allows 0.13 fewer runs than with its usual starter (≈10 weighted starts) |
| Elo ratings | BOS +13 Elo | BOS 51.9% | |
| Market-implied ratings | KC 50.8% | Team strength as past closing lines priced it, same game context | |
| Pre-line forecast | KC 50.4% | 15% Elo, 85% market-implied (log-odds blend) | |
| Forecast | KC 51.0% | 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.
| BOS | Stat | KC |
|---|---|---|
| 29th of 303.7 | Runs scored | 3.928th of 30 |
| 7th of 303.9 | Runs allowed | 4.516th of 30 |
| 18th of 30−0.3 | Margin | −0.625th of 30 |
| 15th of 305–5 | Last 10 | 2–827th of 30 |
| 12th of 3013–13 | Road vs home | 13–1216th of 30 |
| 7th of 301506 | Opponent Elo | 150017th of 30 |
| 13th of 301512 | Elo rating | 148819th 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 |  BOS |  KC |
|---|---|---|
| Run line | 20–28 | 25–24 |
| Last 10 | 7–3 | 5–5 |
| Favorite | 10–19 | 11–15 |
| Underdog | 10–9 | 14–9 |
| Overs–unders | 21–26–1 | 22–26–1 |
| Overs–unders, last 10 | 2–8 | 6–4 |
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
BOS 15–6 KC in their last 21 meetings; the forecast called 14 of 21.