Chicago Cubs at Boston Red Sox, 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 BOS.
Game center
From the ESPN box score.
Top performers
Cubs- Seiya SuzukiBatting2-3
- David PetersonPitching5.0 IP, 0 ER, 6 K
Red Sox- Wilyer AbreuBatting1-4, 2 RBI
- Jedixson PaezPitching5.0 IP, 0 ER, 5 K
Scoring summary
- 8Abreu doubled to center, Jones scored and Kiner-Falefa scored.0–2
The pick
Reconstructed from what was known before the game: the ratings at that point and the closing line.
Cubs 52%
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
- CHC 52%
- ML CHC -120 / BOS -101
- Pre-line forecast
- CHC 53%
- Elo + market-implied
- Elo ratings
- CHC 50%
- Ratings vs. market
- −2.4 pts
- CHC: Elo 49.7%, market 52.1%
- Fair odds
- CHC -109
- BOS +109 · the forecast as odds, no margin
- Pregame projection
- CHC 3.3 – 3.2 BOS
- Margin from the forecast, posted total 6.5
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 | CHC | BOS | Why |
|---|---|---|---|
| Team rating | 1542 | 1535 | Elo entering the game; 1500 is league average |
| Home field | — | +18 | Worth 18 Elo in MLB |
| Starting pitchers | −7 | −15 | CHC: David Peterson: team allows 0.34 more runs than with its usual starter (≈10 weighted starts) · BOS: Brayan Bello: team allows 0.76 more runs than with its usual starter (≈10 weighted starts) |
| Elo ratings | BOS +2 Elo | BOS 50.3% | |
| Market-implied ratings | CHC 53.3% | Team strength as past closing lines priced it, same game context | |
| Pre-line forecast | CHC 52.7% | 15% Elo, 85% market-implied (log-odds blend) | |
| Forecast | CHC 52.1% | 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.
| CHC | Stat | BOS |
|---|---|---|
| 1st of 305.3 | Runs scored | 4.322nd of 30 |
| 12th of 304.4 | Runs allowed | 3.83rd of 30 |
| 3rd of 30+0.9 | Margin | +0.56th of 30 |
| 12th of 305–5 | Last 10 | 4–619th of 30 |
| 7th of 3042–37 | Road vs home | 40–3919th of 30 |
| 12th of 301501 | Opponent Elo | 150113th of 30 |
| 4th of 301542 | Elo rating | 15356th 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 |  CHC |  BOS |
|---|---|---|
| Run line | 78–82 | 78–82 |
| Last 10 | 4–6 | 3–7 |
| Favorite | 43–66 | 43–61 |
| Underdog | 35–16 | 35–21 |
| Overs–unders | 87–64–9 | 71–85–4 |
| Overs–unders, last 10 | 7–3 | 2–8 |
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
CHC 4–6 BOS in their last 10 meetings; the forecast called 5 of 10.