Roy Halladay – 2,066The Top 10 Major League Baseball career strikeout-per-nine innings leaders ( since 1900 , through games of September 27 , 2012 , minimum 1,000 IP ) : Historical Leaders , K/9 at mlb.com , retrieved September 26 , 2012 # Randy Johnson – 10.61 # Kerry Wood – 10.32 # Pedro Martínez – 10.04 # Tim Lincecum - 9.78 # Nolan Ryan – 9.55 # Trevor Hoffman – 9.36 # Sandy Koufax – 9.28 # Oliver Perez – 9.08 # Sam McDowell – 8.86 # Johan Santana – 8.83The Top 5 Major League Baseball single season strikeout-per-nine innings leaders ( since 1900 , through games of September 27 , 2012 , minimum 1.0 IP per team game ) : # Randy Johnson , 2001 – 13.41
In September 2012 , Tim Lincecum and Oliver Perez were among the top 10 players with higher numbers of strikeouts per nine innings with under 9.77 and under 9.08 respectively .