Burnett whiffing hitters, defying time
Making hitters miss is a young man's craft. As a pitcher ages, his strikeout rate tends to erode.
Hurlers younger than age 30 have struck out 7.5 batters per nine innings over the past three seasons. The 30-plus crowd, meanwhile, has whiffed 7.0 hitters per nine frames. Of the top 10 qualified starting pitchers in K/9 this year, nine are in their 20s, and five are 25 or younger.
The Pirates' A.J. Burnett cares little for Father Time. The 36-year-old has struck out a career-high 9.9 batters per nine innings entering his Saturday start, fifth-best in the majors and the second-highest single-season strikeout rate for a Pirates starter throwing at least 120 innings (then-22-year-old Oliver Perez racked up 11 K/9 in 2004).
Burnett's surge puts him in elite company among graybeard starting pitchers. He has the 10th-highest single-season strikeout rate for a starter 36 or older, trailing only ageless wonders like Randy Johnson and Nolan Ryan:
Highest single-season K/9 for starter age 36 or older (120+IP):
Pitcher Year Age K/9
Randy Johnson 2001 37 13.4
Randy Johnson 2000 36 12.6
Randy Johnson 2002 38 11.6
Nolan Ryan 1987 40 11.5
Nolan Ryan 1989 42 11.3
Randy Johnson 2004 40 10.6
Nolan Ryan 1991 44 10.6
Curt Schilling 2003 36 10.4
Nolan Ryan 1990 43 10.2
A.J. Burnett 2013 36 9.9
When it comes to strikeouts, Burnett has little competition among older Pirates starters.
Jim Bunning has the second-highest single-season strikeout rate among Pirates starters 36 or older, with 7.2 K/9 in 1969 before the 37-year-old was traded to the Dodgers.
While strikeout rates are at historic highs, Burnett's K/9 is 38 percent better than the league average for starting pitchers compared to 16 percent for Bunning in '69.
Burnett's curveball is his put-away pitch, but his swinging strike rate with the offering hasn't changed much between 2012 (20.3 percent) and 2013 (20.1 percent). He has raised his strikeout rate mostly by missing more bats with his fastball and changeup:
A look at Burnett's strikeout rates using his fastball and changeup during the past two seasons:
Pitch 2012 2013 MLB avg.
Fastball 4.0 % 5.8 % 6.0 %
Changeup 7.5 % 11.6 % 12.6 %