Arizona Diamondbacks at Boston Red Sox, MLB forecast
You didn't pick this one.
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
Diamondbacks- Tim TawaBatting2-4
- Zack LittellPitching3.2 IP, 6 ER, 0 K
Red Sox- Willson ContrerasBatting2-4, 1 HR, 1 RBI
- Brayan BelloPitching4.2 IP, 1 ER, 3 K
Scoring summary
- 7Abreu singled to center, Rafaela scored.1–11
- 7Gasper homered to right (343 feet).1–10
- 6Rutschman doubled to left, Abreu scored.1–9
- 6Abreu singled to right, Rafaela scored.1–8
- 6Perdomo hit sacrifice fly to left, Vargas scored.1–7
- 5Gasper grounded out to second, Durbin scored.0–7
- 5Monasterio hit sacrifice fly to left, Rutschman scored, Durbin to third.0–6
- 5Contreras homered to left (342 feet).0–5
- 4Rafaela doubled to right, Sogard scored.0–4
- 3Durbin singled to right, Contreras scored.0–3
- 2Sogard doubled to center, White scored.0–2
- 2White singled to left, Durbin scored.0–1
The pick
Reconstructed from what was known before the game: the ratings at that point and the closing line.
Red Sox 56%
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
- BOS 56%
- ML ARI +125 / BOS -134
- Pre-line forecast
- BOS 58%
- Elo + market-implied
- Elo ratings
- BOS 54%
- Ratings vs. market
- −2.3 pts
- BOS: Elo 54.0%, market 56.3%
- Fair odds
- BOS -129
- ARI +129 · the forecast as odds, no margin
- Pregame projection
- ARI 4.2 – 4.8 BOS
- Margin from the forecast, posted total 9
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 | ARI | BOS | Why |
|---|---|---|---|
| Team rating | 1516 | 1540 | Elo entering the game; 1500 is league average |
| Home field | — | +18 | Worth 18 Elo in MLB |
| Starting pitchers | +5 | −10 | ARI: Mitch Bratt: team allows 0.23 fewer runs than with its usual starter (≈5 weighted starts) · BOS: Alec Gamboa (no track record yet) |
| Elo ratings | BOS +28 Elo | BOS 54.0% | |
| Market-implied ratings | BOS 58.5% | Team strength as past closing lines priced it, same game context | |
| Pre-line forecast | BOS 57.8% | 15% Elo, 85% market-implied (log-odds blend) | |
| Forecast | BOS 56.3% | 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.
| ARI | Stat | BOS |
|---|---|---|
| 14th of 304.5 | Runs scored | 4.417th of 30 |
| 15th of 304.4 | Runs allowed | 3.82nd of 30 |
| 12th of 30+0.1 | Margin | +0.77th of 30 |
| 10th of 305–5 | Last 10 | 3–726th of 30 |
| 13th of 3030–32 | Road vs home | 29–3122nd of 30 |
| 13th of 301500 | Opponent Elo | 150010th of 30 |
| 11th of 301516 | Elo rating | 15404th 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 |  ARI |  BOS |
|---|---|---|
| Run line | 69–56 | 62–62 |
| Last 10 | 6–4 | 3–7 |
| Favorite | 20–33 | 33–45 |
| Underdog | 49–23 | 29–17 |
| Overs–unders | 50–67–8 | 56–64–4 |
| Overs–unders, last 10 | 3–7 | 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
ARI 6–3 BOS in their last 9 meetings; the forecast called 1 of 9.