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
96
66
.593
Mets Mets
83
79
.512
13.0
NL Central W L PCT GB
Brewers Brewers
97
65
.599
Cubs Cubs
92
70
.568
5.0
NL West W L PCT GB
Dodgers Dodgers
93
69
.574
Padres Padres
90
72
.556
3.0
AL East W L PCT GB
Blue Jays Blue Jays
94
68
.580
Yankees Yankees
94
68
.580
AL Central W L PCT GB
Guardians Guardians
88
74
.543
Tigers Tigers
87
75
.537
1.0
AL West W L PCT GB
Mariners Mariners
90
72
.556
Astros Astros
87
75
.537
3.0

MLB 2025 Scores & Schedule

Scores

DATE MATCHUP SCORE
Mon
9/15
ATL ATL
@
WSH WSH
6-3
Mon
9/15
SDP SDP
@
NYM NYM
3-8
Mon
9/15
NYY NYY
@
MIN MIN
10-9
Tue
9/16
CHC CHC
@
PIT PIT
8-4
Tue
9/16
CIN CIN
@
STL STL
6-2

Schedule

DATE MATCHUP TIME (ET)
Fri
10/17
TOR TOR
@
SEA SEA
6:08 PM
Fri
10/17
MIL MIL
@
LAD LAD
8:38 PM
Sat
10/18
MIL MIL
@
LAD LAD
8:08 PM
Sun
10/19
SEA SEA
@
TOR TOR
8:03 PM
Mon
10/20
LAD LAD
@
MIL MIL
5:08 PM