Last season Carlos Marmol set the all-time record by striking out 16.0 batters per nine innings, becoming the first pitcher in baseball history with a strikeout rate above 15.0.
Marmol’s record is probably safe, but Dodgers reliever Kenley Jansen looks set to join him in the 15-plus club. Last night Jansen closed out a 3-2 victory for his fourth save of the season and struck out the side in the process, giving him 83 strikeouts in 48 innings overall.
That works out to 15.6 strikeouts per nine innings, which is the second-highest rate of all time:
YEAR SO/9
Carlos Marmol 2010 16.0
KENLEY JANSEN 2011 15.6
Eric Gagne 2003 15.0
Billy Wagner 1999 15.0
Brad Lidge 2004 14.9
Predictably the top five spots all belong to relievers from the past 15 years. In terms of strikeout rates for starting pitchers Randy Johnson has the all-time record with 13.4 in 2001, when he whiffed 372 batters in 250 innings for the Diamondbacks.
Jansen, who began his pro career as a light-hitting catcher and didn’t move to the mound until 2009, has a 2.28 ERA, .156 opponents’ batting average, and 124 strikeouts in 75 innings as a big leaguer.