bayesRatings

Royals at Cardinals

MLB · Friday, May 15 · 7:15 PM CT · Busch Stadium · Final KC 4 – STL 5
← MLB / May 15

Final Box Score

from the game summary
Team1234567891011THE
KC00020100010470
STL000210000115120
Team box
KC·STL
7
hits
12
0
home runs
2
7
walks
5
7
strikeouts
11
156
pitches thrown
158
0
errors
0
Top hitters
PlayerTeamH-ABRHRRBI
Jordan WalkerSTL3-5112
Pedro PagesSTL1-4111
Bobby Witt Jr.KC2-5001
Carter JensenKC2-4001
Alec BurlesonSTL2-5001
Isaac CollinsKC0-2002
Pitchers
PitcherTeamIPHERBBK
Michael WachaKC6.05315
Steven Cruz (L)KC0.21010
Dustin MaySTL6.04343
Gordon Graceffo (W)STL1.00010

For context, not in our forecast.

Game Flow

score margin
STL +3
KC +3
1234567891011
largest lead: STL 1 · KC 2lead changes: 3

For context, not in our forecast.

Final · our forecast was KC 47%, STL 53% · Updated May 15

Expected margin
Even
Expected score
STL 4.2 – 4.2 KC
Expected total
8.4
RoyalsThe matchupCardinals
+114Our fair odds−114
4.2Expected runs4.2
−0.03Power rating+0.01
4.1Runs / game4.6
4.6Allowed / game4.6
7.9Hits / game8.1
1.00Home runs / game1.14
3.5Walks drawn / game3.5
19−25Season record25−18
4−6Last 105−5

Prediction markets

Kalshi · Polymarket US · ProphetX · Novig
KC chance · STL chance
Our model fair46.7%53.3%
Kalshi52.7%52.7%
Polymarket USno two-sided price
ProphetXno two-sided price
Novigno two-sided price
Full price table
TeamOur modelfairKalshipre-game · 7:15 PM CTPolymarket US ProphetX Novig 
Moneyline
KCKansas City Royals+11447%−11252.7%———
STLSt. Louis Cardinals−11453%−11252.7%———
Spreadabout even
KCKansas City RoyalsPKour margin————
STLSt. Louis CardinalsPKour margin————
Totalwe expect 8.4
Over8.4our total————
Under8.4our 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
Kansas City Royals by 12 runs: <1%Kansas City Royals by 11 runs: <1%Kansas City Royals by 10 runs: 1%Kansas City Royals by 9 runs: 1%Kansas City Royals by 8 runs: 1%Kansas City Royals by 7 runs: 2%Kansas City Royals by 6 runs: 3%Kansas City Royals by 5 runs: 4%Kansas City Royals by 4 runs: 6%Kansas City Royals by 3 runs: 7%Kansas City Royals by 2 runs: 10%Kansas City Royals by 1 run: 11%St. Louis Cardinals by 1 run: 18%St. Louis Cardinals by 2 runs: 10%St. Louis Cardinals by 3 runs: 7%St. Louis Cardinals by 4 runs: 5%St. Louis Cardinals by 5 runs: 4%St. Louis Cardinals by 6 runs: 3%St. Louis Cardinals by 7 runs: 2%St. Louis Cardinals by 8 runs: 1%St. Louis Cardinals by 9 runs: 1%St. Louis Cardinals by 10 runs: 1%St. Louis Cardinals by 11 runs: <1%St. Louis Cardinals by 12 runs: <1%
← KC wins bySTL wins by →
St. Louis Cardinals wins by 2 or more35%
St. Louis Cardinals wins by 3 or more25%
Kansas City Royals wins by 2 or more36%
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

8.4 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: 1%18 runs: 1%19 runs: 1%20 runs: <1%21 runs: <1%22 runs: <1%
Total runs, both teams
Total over 6.565%
Total over 8.545%
Total over 10.528%
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
KCMichael Wacha SP · last 3 starts: 19.0 IP, 2.84 ERA, 14 Kstarted
STLDustin May SP · last 3 starts: 18.0 IP, 3.50 ERA, 12 Kstarted

Starting pitchers are part of our forecast.

Rest and Schedule

before this game
KC·STL
May 14 at CHW
last game
May 14 at ATH
0 days
days of rest
0 days
6
games in last 7 days
6
4th straight road game
home / road
home after a road game

For context, not in our forecast.

Team Comparison

2026 season · box-score averages from 43+ games
KC·STL
−0.03
rating (0 = average)
+0.01
4.1
runs / game
4.6
4.6
runs allowed / game
4.6
19−25
season record
25−18
13−10
home record
10−10
6−15
away record
15−8
L4
streak
W1
4−6
last 10
5−5
7.9
hits / game
8.1
1.00
home runs / game
1.14
3.5
walks drawn / game
3.5
8.2
batter strikeouts / game
8.3
8.5
pitcher strikeouts / game
7.3
0.36
errors / game
0.47

Rating Trend

KC · STL · 51 days
Kansas City RoyalsSt. Louis Cardinals
Rating (0 = average team)

Head to Head

last 10 meetings · STL 4−6
Jun 5, 2025at STLKC 7 − 5
Jun 5, 2025at STLSTL 6 − 5
Jun 3, 2025at STLKC 10 − 7
May 18, 2025at KCKC 2 − 1
May 17, 2025at KCSTL 1 − 0
May 16, 2025at KCSTL 10 − 3
Aug 10, 2024at KCKC 8 − 3
Aug 9, 2024at KCSTL 8 − 5
Jul 10, 2024at STLKC 8 − 5
Jul 10, 2024at STLKC 6 − 4

KC · Last 10

4−6 · streak L4
May 14at CHW2 − 6L
May 13at CHW5 − 6L
May 12at CHW5 − 6L
May 10vs DET3 − 6L
May 9vs DET5 − 1W
May 8vs DET4 − 3W
May 7vs CLE5 − 8L
May 6vs CLE1 − 3L
May 5vs CLE5 − 3W
May 4vs CLE6 − 2W

STL · Last 10

5−5 · streak W1
May 14at ATH5 − 4W
May 13at ATH2 − 6L
May 12at ATH6 − 4W
May 10at SD2 − 3L
May 9at SD2 − 4L
May 8at SD6 − 0W
May 7at SD2 − 1W
May 6vs MIL2 − 6L
May 4vs MIL6 − 3W
May 3vs LAD1 − 4L