Arizona Diamondbacks at Boston Red Sox, MLB forecast
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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- Eugenio SuarezBatting1-4, 2 RBI
- Zac GallenPitching6.0 IP, 0 ER, 9 K
Red Sox- Masataka YoshidaBatting1-4, 1 RBI
- Kutter CrawfordPitching5.0 IP, 2 ER, 3 K
Scoring summary
- 9Yoshida doubled to center, Refsnyder scored.4–1
- 9Pitch 2 : Ball In Play4–1
- 9Pitch 1 : Ball 14–1
- 7Guillorme scored on Bernardino wild pitch, McCarthy to second on wild pitch by Bernardino, Carroll to third on wild pitch by Bernardino.4–0
- 7Guillorme scored on Bernardino wild pitch, McCarthy to second on wild pitch by Bernardino, Carroll to third on wild pitch by Bernardino.4–0
- 7McCarthy walked, Perdomo scored, Carroll to second, Guillorme to third.3–0
- 7Pitch 6 : Ball 43–0
- 7Pitch 5 : Strike 2 Foul3–0
- 7Pitch 4 : Ball 33–0
- 7Pitch 3 : Strike 1 Looking3–0
- 7Pitch 2 : Ball 23–0
- 7Pitch 1 : Ball 13–0
- 4Suárez doubled to center, Bell scored and Pederson scored.2–0
- 4Pitch 1 : Ball In Play2–0
The pick
Reconstructed from what was known before the game: the ratings at that point and the closing line.
Red Sox 54%
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
- BOS 54%
- ML ARI +110 / BOS -130
- Pre-line forecast
- BOS 50%
- Elo + market-implied
- Elo ratings
- BOS 47%
- Ratings vs. market
- −7.4 pts
- BOS: Elo 46.9%, market 54.3%
- Fair odds
- BOS -119
- ARI +119 · the forecast as odds, no margin
- Pregame projection
- ARI 4.6 – 4.9 BOS
- Margin from the forecast, posted total 9.5
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 | ARI | BOS | Why |
|---|---|---|---|
| Team rating | 1536 | 1503 | Elo entering the game; 1500 is league average |
| Home field | — | +18 | Worth 18 Elo in MLB |
| Starting pitchers | +5 | −2 | ARI: Zac Gallen: team allows 0.23 fewer runs than with its usual starter (≈10 weighted starts) · BOS: Kutter Crawford: team allows 0.10 more runs than with its usual starter (≈10 weighted starts) |
| Elo ratings | ARI +22 Elo | ARI 53.1% | |
| Market-implied ratings | BOS 50.3% | Team strength as past closing lines priced it, same game context | |
| Pre-line forecast | ARI 50.3% | 15% Elo, 85% market-implied (log-odds blend) | |
| Forecast | BOS 54.3% | 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.
| ARI | Stat | BOS |
|---|---|---|
| 1st of 305.3 | Runs scored | 4.95th of 30 |
| 23rd of 304.7 | Runs allowed | 4.826th of 30 |
| 7th of 30+0.7 | Margin | +0.115th of 30 |
| 2nd of 307–3 | Last 10 | 5–511th of 30 |
| 6th of 3036–30 | Road vs home | 29–3427th 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 | 69–60 | 58–70 |
| Last 10 | 7–3 | 6–4 |
| Favorite | 27–35 | 21–46 |
| Underdog | 42–25 | 37–24 |
| Overs–unders | 74–54–1 | 68–58–2 |
| Overs–unders, last 10 | 7–3 | 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 2–2 BOS in their last 4 meetings; the forecast called 1 of 4.