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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AL East W L PCT GB
Blue Jays Blue Jays
55
41
.573
Yankees Yankees
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43
.552
2.0
AL Central W L PCT GB
Tigers Tigers
59
38
.608
Twins Twins
47
49
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AL West W L PCT GB
Astros Astros
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Mariners Mariners
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MLB 2025 Scores & Schedule

Scores

DATE MATCHUP SCORE
Sat
6/28
STL STL
@
CLE CLE
7-0
Sat
6/28
PHI PHI
@
ATL ATL
2-1
Sat
6/28
TBR TBR
@
BAL BAL
1-5
Sat
6/28
ATH ATH
@
NYY NYY
5-12
Sat
6/28
TOR TOR
@
BOS BOS
5-3

Schedule

DATE MATCHUP TIME (ET)
Fri
7/18
BOS BOS
@
CHC CHC
2:20 PM
Fri
7/18
CWS CWS
@
PIT PIT
6:40 PM
Fri
7/18
SDP SDP
@
WSH WSH
6:45 PM
Fri
7/18
LAA LAA
@
PHI PHI
6:45 PM
Fri
7/18
SFG SFG
@
TOR TOR
7:07 PM