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Diamondbacks at Red Sox

MLB · Wednesday, Aug 19 · 3:10 PM CT · Fenway Park · Final ARI 7 – BOS 6

Final Box Score

from the game summary
Team12345678910THE
ARI00003200027100
BOS1010030001690
Team box
ARI·BOS
10
hits
9
1
home runs
3
8
walks
2
10
strikeouts
10
161
pitches thrown
201
0
errors
0
Top hitters
PlayerTeamH-ABRHRRBI
Mickey GasperBOS1-3113
Lars NootbaarARI1-2112
Jarren DuranBOS2-4111
Nick SogardBOS2-4111
Nolan ArenadoARI2-5101
Gabriel MorenoARI1-4102
Pitchers
PitcherTeamIPHERBBK
Brandon PfaadtARI5.27508
Jonathan Loaisiga (W)ARI2.01000
Payton TolleBOS5.06326
Jovani Moran (L)BOS1.01130

For context, not in our forecast.

Game Flow

score margin
BOS +3
ARI +3
12345678910
largest lead: BOS 2 · ARI 3lead changes: 1

For context, not in our forecast.

Final · our forecast was ARI 44%, BOS 56% · Updated Aug 19

Expected margin
BOS by 0.7
Expected score
BOS 4.6 – 3.9 ARI
Expected total
8.5
DiamondbacksThe matchupRed Sox
+125Our fair odds−125
3.9Expected runs4.6
+0.04Power rating+0.20
4.5Runs / game4.5
4.5Allowed / game3.8
8.1Hits / game8.4
0.98Home runs / game1.02
3.3Walks drawn / game3.2
66−61Season record68−58
4−6Last 104−6

Prediction markets

Kalshi · Polymarket US · ProphetX · Novig
ARI chance · BOS chance
Our model fair44.4%55.6%
Kalshi42.7%61.7%
Polymarket USno two-sided price
ProphetXno two-sided price
Novigno two-sided price
Full price table
TeamOur modelfairKalshipre-game · 3:10 PM CTPolymarket US ProphetX Novig 
Moneyline
ARIArizona Diamondbacks+12544%+13442.7%———
BOSBoston Red Sox−12556%−16161.7%———
SpreadBOS by 0.7
ARIArizona Diamondbacks+0.7our margin————
BOSBoston Red Sox−0.7our margin————
Totalwe expect 8.5
Over8.5our total————
Under8.5our total————

These are each venue’s last prices before the start (Kalshi’s moneyline: its pre-game close). Odds are the price to buy that side now, taker fee included; the small percent is the implied chance of that same price. Highlighted is the best price in the row among venues on the same line. — means not listed (hover or tap for why). A market price is not the true chance of winning.

Margin range

Boston Red Sox by 0.7 expected
Arizona Diamondbacks by 13 runs: <1%Arizona Diamondbacks by 12 runs: <1%Arizona Diamondbacks by 11 runs: <1%Arizona Diamondbacks by 10 runs: <1%Arizona Diamondbacks by 9 runs: 1%Arizona Diamondbacks by 8 runs: 1%Arizona Diamondbacks by 7 runs: 1%Arizona Diamondbacks by 6 runs: 2%Arizona Diamondbacks by 5 runs: 3%Arizona Diamondbacks by 4 runs: 5%Arizona Diamondbacks by 3 runs: 6%Arizona Diamondbacks by 2 runs: 9%Arizona Diamondbacks by 1 run: 15%Boston Red Sox by 1 run: 14%Boston Red Sox by 2 runs: 11%Boston Red Sox by 3 runs: 8%Boston Red Sox by 4 runs: 6%Boston Red Sox by 5 runs: 5%Boston Red Sox by 6 runs: 4%Boston Red Sox by 7 runs: 3%Boston Red Sox by 8 runs: 2%Boston Red Sox by 9 runs: 1%Boston Red Sox by 10 runs: 1%Boston Red Sox by 11 runs: 1%Boston Red Sox by 12 runs: <1%Boston Red Sox by 13 runs: <1%
← ARI wins byBOS wins by →
Boston Red Sox wins by 2 or more42%
Boston Red Sox wins by 3 or more31%
Arizona Diamondbacks wins by 2 or more30%
Decided by one run29%

Centered on the expected margin above; shape from each team's expected runs, with ties after nine settled as one-run games, matched to 14,698 past MLB games.

Total range

8.5 expected
1 runs: 2%2 runs: 2%3 runs: 7%4 runs: 5%5 runs: 11%6 runs: 8%7 runs: 12%8 runs: 8%9 runs: 10%10 runs: 6%11 runs: 7%12 runs: 4%13 runs: 5%14 runs: 3%15 runs: 3%16 runs: 2%17 runs: 2%18 runs: 1%19 runs: 1%20 runs: <1%21 runs: <1%22 runs: <1%23 runs: <1%
Total runs, both teams
Total over 6.565%
Total over 8.546%
Total over 10.529%
Total from 7 to 1037%

Centered on the expected total above; shape from each team's expected runs, with ties after nine settled as one-run games, matched to 14,698 past MLB games.

Starting Pitchers

from the box score
ARIBrandon Pfaadt SP · last 3 starts: 20.2 IP, 0.00 ERA, 12 Kstarted
BOSPayton Tolle SP · last 3 starts: 20.0 IP, 1.35 ERA, 25 Kstarted

Starting pitchers are part of our forecast.

Rest and Schedule

before this game
ARI·BOS
Aug 18 at BOS
last game
Aug 18 vs ARI
0 days
days of rest
0 days
6
games in last 7 days
7
6th straight road game
home / road
3rd straight home game

For context, not in our forecast.

Team Comparison

2026 season · box-score averages from 126+ games
ARI·BOS
+0.04
rating (0 = average)
+0.20
4.5
runs / game
4.5
4.5
runs allowed / game
3.8
66−61
season record
68−58
36−27
home record
31−31
30−34
away record
37−27
L3
streak
W2
4−6
last 10
4−6
8.1
hits / game
8.4
0.98
home runs / game
1.02
3.3
walks drawn / game
3.2
7.3
batter strikeouts / game
8.1
6.7
pitcher strikeouts / game
8.5
0.38
errors / game
0.49

Rating Trend

ARI · BOS · 144 days
Arizona DiamondbacksBoston Red Sox
Rating (0 = average team)

Head to Head

last 10 meetings · BOS 4−6
Aug 18at BOSBOS 9 − 4
Aug 17at BOSBOS 11 − 1
Sep 7, 2025at ARIBOS 7 − 4
Sep 6, 2025at ARIARI 5 − 1
Sep 5, 2025at ARIARI 10 − 5
Aug 25, 2024at BOSARI 7 − 5
Aug 24, 2024at BOSARI 4 − 1
Aug 23, 2024at BOSARI 12 − 2
May 28, 2023at ARIARI 4 − 2
May 27, 2023at ARIBOS 2 − 1

ARI · Last 10

4−6 · streak L3
Aug 18at BOS4 − 9L
Aug 17at BOS1 − 11L
Aug 16at ATL3 − 5L
Aug 15at ATL10 − 3W
Aug 14at ATL2 − 0W
Aug 12vs COL4 − 6L
Aug 11vs COL2 − 3L
Aug 10vs COL9 − 0W
Aug 9vs LAD4 − 2W
Aug 8vs LAD1 − 2L

BOS · Last 10

4−6 · streak W2
Aug 18vs ARI9 − 4W
Aug 17vs ARI11 − 1W
Aug 16at PIT3 − 8L
Aug 15at PIT4 − 0W
Aug 14at PIT4 − 8L
Aug 13at TOR7 − 0W
Aug 12at TOR4 − 6L
Aug 11at TOR3 − 5L
Aug 10at TOR1 − 2L
Aug 9vs ATH3 − 4L