bayesRatings

Diamondbacks at Royals

MLB · Tuesday, Sep 8 · 6:40 PM CT · Kauffman Stadium · Final ARI 5 – KC 3
← MLB / Sep 8

Final Box Score

from the game summary
Team1234567891011THE
ARI00000001112591
KC00000000210371
Team box
ARI·KC
9
hits
7
1
home runs
1
7
walks
7
5
strikeouts
8
170
pitches thrown
191
1
errors
1
Top hitters
PlayerTeamH-ABRHRRBI
Tim TawaARI3-5112
John RaveKC1-3112
Ketel MarteARI1-3101
Lourdes Gurriel Jr.ARI1-3101
Lars NootbaarARI2-3000
Vinnie PasquantinoKC1-4001
Pitchers
PitcherTeamIPHERBBK
Corbin BurnesARI3.02022
Blake Walston (W)ARI2.00032
Michael WachaKC6.03044
Anthony Gose (L)KC1.01000

For context, not in our forecast.

Game Flow

score margin
KC +3
ARI +3
1234567891011
largest lead: KC 0 · ARI 2lead changes: 0

For context, not in our forecast.

Final · our forecast was ARI 52%, KC 48% · Updated Sep 8

Expected margin
Even
Expected score
ARI 4.7 – 4.3 KC
Expected total
9.0
DiamondbacksThe matchupRoyals
−109Our fair odds+109
4.7Expected runs4.3
+0.05Power rating−0.12
4.4Runs / game4.3
4.4Allowed / game4.9
8.1Hits / game8.3
0.97Home runs / game1.04
3.3Walks drawn / game3.2
77−68Season record64−81
6−4Last 104−6

Prediction markets

Kalshi · Polymarket US · ProphetX · Novig
ARI chance · KC chance
Our model fair52.1%47.9%
Kalshi50.7%53.7%
Polymarket USno two-sided price
ProphetXno two-sided price
Novigno two-sided price
Full price table
TeamOur modelfairKalshipre-game · 6:40 PM CTPolymarket US ProphetX Novig 
Moneyline
ARIArizona Diamondbacks−10952%−10350.7%———
KCKansas City Royals+10948%−11653.7%———
Spreadabout even
ARIArizona Diamondbacks−0.4our margin————
KCKansas City Royals+0.4our margin————
Totalwe expect 9.0
Over9.0our total————
Under9.0our 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

Even game 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: 2%Arizona Diamondbacks by 7 runs: 2%Arizona Diamondbacks by 6 runs: 3%Arizona Diamondbacks by 5 runs: 5%Arizona Diamondbacks by 4 runs: 6%Arizona Diamondbacks by 3 runs: 8%Arizona Diamondbacks by 2 runs: 10%Arizona Diamondbacks by 1 run: 13%Kansas City Royals by 1 run: 15%Kansas City Royals by 2 runs: 9%Kansas City Royals by 3 runs: 7%Kansas City Royals by 4 runs: 5%Kansas City Royals by 5 runs: 4%Kansas City Royals by 6 runs: 3%Kansas City Royals by 7 runs: 2%Kansas City Royals by 8 runs: 1%Kansas City Royals by 9 runs: 1%Kansas City Royals by 10 runs: 1%Kansas City Royals by 11 runs: <1%Kansas City Royals by 12 runs: <1%Kansas City Royals by 13 runs: <1%
← ARI wins byKC wins by →
Arizona Diamondbacks wins by 2 or more40%
Arizona Diamondbacks wins by 3 or more30%
Kansas City Royals wins by 2 or more33%
Decided by one run28%

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

9.0 expected
1 runs: 2%2 runs: 2%3 runs: 6%4 runs: 5%5 runs: 10%6 runs: 7%7 runs: 12%8 runs: 8%9 runs: 10%10 runs: 7%11 runs: 8%12 runs: 5%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%24 runs: <1%
Total runs, both teams
Total over 7.558%
Total over 9.540%
Total over 11.525%
Total from 8 to 1133%

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
ARICorbin Burnes SP · last 3 starts: 18.2 IP, 2.89 ERA, 20 Kstarted
KCMichael Wacha SP · last 3 starts: 21.0 IP, 1.71 ERA, 23 Kstarted

Starting pitchers are part of our forecast.

Rest and Schedule

before this game
ARI·KC
Sep 7 at KC
last game
Sep 7 vs ARI
0 days
days of rest
0 days
6
games in last 7 days
7
5th straight road game
home / road
8th straight home game

For context, not in our forecast.

Team Comparison

2026 season · box-score averages from 145+ games
ARI·KC
+0.05
rating (0 = average)
−0.12
4.4
runs / game
4.3
4.4
runs allowed / game
4.9
77−68
season record
64−81
41−31
home record
38−35
36−37
away record
26−46
W3
streak
L1
6−4
last 10
4−6
8.1
hits / game
8.3
0.97
home runs / game
1.04
3.3
walks drawn / game
3.2
7.3
batter strikeouts / game
7.8
6.9
pitcher strikeouts / game
7.3
0.37
errors / game
0.44

Rating Trend

ARI · KC · 164 days
Arizona DiamondbacksKansas City Royals
Rating (0 = average team)

Head to Head

last 10 meetings · KC 4−6
Sep 7at KCARI 5 − 4
Jul 6, 2025at ARIKC 4 − 0
Jul 5, 2025at ARIARI 7 − 1
Jul 4, 2025at ARIKC 9 − 3
Jul 24, 2024at KCARI 8 − 6
Jul 23, 2024at KCARI 6 − 2
Jul 22, 2024at KCKC 10 − 4
Apr 26, 2023at ARIARI 2 − 0
Apr 25, 2023at ARIKC 5 − 4
Apr 24, 2023at ARIARI 5 − 4

ARI · Last 10

6−4 · streak W3
Sep 7at KC5 − 4W
Sep 6at HOU3 − 2W
Sep 5at HOU4 − 3W
Sep 4at HOU1 − 3L
Sep 2vs PHI1 − 0W
Sep 1vs PHI1 − 7L
Aug 31vs PHI1 − 2L
Aug 29at SF2 − 7L
Aug 29at SF7 − 1W
Aug 28at SF10 − 6W

KC · Last 10

4−6 · streak L1
Sep 7vs ARI4 − 5L
Sep 6vs TOR6 − 1W
Sep 5vs TOR3 − 4L
Sep 4vs TOR2 − 9L
Sep 3vs MIA7 − 3W
Sep 2vs MIA6 − 9L
Sep 1vs MIA3 − 6L
Aug 30at CLE1 − 11L
Aug 29at CLE8 − 3W
Aug 28at CLE3 − 0W