Matt Kilroy has struck out the most hitters in a season, with 513 strikeouts in his rookie season in 1886.

which pitcher has the most strikeouts in a season
1886Kilroy1886Ramsey1884Daily1884Shaw1884Radbourn1884Buffinton1884Hecker1973Ryan1965Koufax1884Sweeney2001Johnson1884Galvin1889Baldwin1974Ryan1999Johnson1883Keefe1887Ramsey1904Waddell1946Feller2000Johnson1884Henderson1884Welch1883Whitney1884McCormick1977Ryan513499483451441417385383382374372369368367364359355349348347346345345343341
NAMESEASONTMGSOWLW%GSCGGFSHOSVIPHTBFRERHRBBIBBHBPWPERAWHIPK/9H/9BB/9K/BBERA-FIPFIP-PRAA
Matt KilroyMatt Kilroy1886BALBAL685132934.4606866050583.04762,4693502181018219613.371.137.927.352.812.821002.607747
Toad RamseyToad Ramsey1886LOU674993827.5856766030588.24472,477297160320712352.451.117.636.833.162.41712.597654.7
Hugh DailyHugh Daily1884TOT584832828.5005856050500.24462,0762681351172502.431.038.688.021.296.71812.067927.4
Dupee ShawDupee Shaw1884TOT674513033.4766660150543.14462,2442811399109242.301.027.477.391.814.14772.438129
Old Hoss RadbournOld Hoss Radbourn1884PRO754415912.83173732112678.25282,6722161041898341.380.925.857.001.304.50482.758431.9
Charlie BuffintonCharlie Buffinton1884BSNBSN674174816.7506763080587.05062,3832251401576242.150.996.397.761.175.49742.577746.8
Guy HeckerGuy Hecker1884LOU753855220.7227372260670.25262,64923013445616271.800.875.177.060.756.88572.538043
Nolan RyanNolan Ryan1973CALCAL413832116.5683926241326.02381,3551131041816227152.871.2310.576.574.472.36802.486940.9
Sandy KoufaxSandy Koufax1965LADLAD43382268.7654127282335.22161,2979076267145112.040.8610.245.791.905.38631.936147.9
Bill SweeneyBill Sweeney1884BLU623744021.6566058240538.05222,2702941551374432.591.116.268.731.245.05802.619319.5
Randy JohnsonRandy Johnson2001ARIARI35372216.778343120249.21819947469197121882.491.0113.416.522.565.24552.124863.9
Pud GalvinPud Galvin1884BUF723694622.67672710120636.15662,5542541412363161.990.995.228.010.895.86642.888250.9
Mark BaldwinMark Baldwin1889COL633682734.4435954461513.24582,275358206927420833.611.436.458.024.801.341003.5298-3
Nolan RyanNolan Ryan1974CALCAL423672216.5794126130332.22211,392127107182023992.891.279.935.985.461.82852.978420.2
Randy JohnsonRandy Johnson1999ARIARI35364179.6543512020271.22071,079867530703942.481.0212.066.862.325.20532.755957.2
Tim KeefeTim Keefe1883NYM683594127.6036868050619.04882,5172441666108272.410.965.227.101.573.32722.748245.1
Toad RamseyToad Ramsey1887LOU653553727.5786461100561.05442,430358214916716463.431.275.708.732.682.13783.207664.2
Rube WaddellRube Waddell1904PHAPHA463492519.5684639080383.03071,496109695911481.621.048.207.212.143.84611.596241.5
Bob FellerBob Feller1946CLECLE483482615.63442365104371.12771,5121019011153332.181.168.436.713.712.27652.166548.3
Randy JohnsonRandy Johnson2000ARIARI35347197.731358030248.22021,001897323761652.641.1212.567.312.754.57562.535361.1
Hardie HendersonHardie Henderson1884BLABLA523462723.5405250040439.13821,900235128911616452.621.137.097.832.382.98812.878916.5
Mickey WelchMickey Welch1884NYGNYG653453921.6506562140557.15282,37027515512146392.501.215.578.532.362.36853.109214.6
Jim WhitneyJim Whitney1883BSNBSN623453721.6385654512514.04922,101258128735372.241.036.048.610.619.86742.297539.8
Jim McCormickJim McCormick1884TOT663434025.61565632100569.05082,3362631501989152.371.055.438.041.413.85802.97949.6
Nolan RyanNolan Ryan1977CALCAL373411916.5433722040299.01981,272110921220479212.771.3410.265.966.141.67723.117927.9

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