Who was the first pitcher with 20 strikeouts in a game with fewer than 10 IP?

Roger Clemens becomes the first pitcher in MLB history to strike out 20 batters in a nine-inning game.

Interpreted as:
Who was the first pitcher with 20 or more strikeouts in a game with fewer than 10 IP?
NAME DATE TM OPP DEC SO IP GS CG GF SHO SV H TBF R ER HR BB IBB HBP WP
1 Roger Clemens
Roger Clemens
4/29/1986
BOS BOS
vs. SEA vs. SEA
W
20
9.0
1
1
0
0
0
3
30
1
1
1
0
0
0
0
2 Roger Clemens
Roger Clemens
9/18/1996
BOS BOS
@ DET @ DET
W
20
9.0
1
1
0
1
0
5
32
0
0
0
0
0
0
1
3 Kerry Wood
Kerry Wood
5/6/1998
CHC CHC
vs. HOU vs. HOU
W
20
9.0
1
1
0
1
0
1
29
0
0
0
0
0
1
0
4 Randy Johnson
Randy Johnson
5/8/2001
ARI ARI
vs. CIN vs. CIN
20
9.0
1
0
0
0
0
3
29
1
1
0
0
0
0
0
5 Max Scherzer
Max Scherzer
5/11/2016
WSH WSH
vs. DET vs. DET
W
20
9.0
1
1
0
0
0
6
33
2
2
2
0
0
0
0
Results may be incomplete. StatMuse has complete game-level data for innings pitched and strikeouts going back to the 1908 season.
Some of the information used here was obtained free of charge from Retrosheet.

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MLB 2025 Division Standings

NL East W L PCT GB
Phillies Phillies
92
64
.590
Mets Mets
80
76
.513
12.0
NL Central W L PCT GB
Brewers Brewers
95
61
.609
Cubs Cubs
88
68
.564
7.0
NL West W L PCT GB
Dodgers Dodgers
88
68
.564
Padres Padres
85
71
.545
3.0
AL East W L PCT GB
Blue Jays Blue Jays
90
66
.577
Yankees Yankees
88
68
.564
2.0
AL Central W L PCT GB
Tigers Tigers
85
71
.545
Guardians Guardians
84
72
.538
1.0
AL West W L PCT GB
Mariners Mariners
87
69
.558
Astros Astros
84
72
.538
3.0

MLB 2025 Scores & Schedule

Scores

DATE MATCHUP SCORE
Sat
9/6
SEA SEA
@
ATL ATL
18-2
Sat
9/6
CWS CWS
@
DET DET
6-4
Sat
9/6
NYM NYM
@
CIN CIN
2-3
Sat
9/6
PHI PHI
@
MIA MIA
4-5
Sat
9/6
WSH WSH
@
CHC CHC
6-3

Schedule

DATE MATCHUP TIME (ET)
Mon
9/22
WSH WSH
@
ATL ATL
7:15 PM
Mon
9/22
MIL MIL
@
SDP SDP
9:40 PM
Mon
9/22
STL STL
@
SFG SFG
9:45 PM
Tue
9/23
TBR TBR
@
BAL BAL
6:35 PM
Tue
9/23
DET DET
@
CLE CLE
6:40 PM