Deleting the Adjectives: Stephen Strasburg and Strikeout Rate
Like Anthony Rendon, my new column is making its triumphant debut this week. This will mostly be a space for research and statistics based analysis, but we won’t get bogged down in the numbers, they’re just meant to illuminate a small part of the game that may go unseen. So now let’s get on with the show.
So far this season Stephen Strasburg has been striking out batters at a rate of 21.4%. For the typical pitcher that in and of itself is fairly unremarkable, he MLB average is around 18.5%, so 21.4% is solidly above average while not being spectacular. However, for Strasburg, a pitcher with a career K% of 30.4%, it is a startlingly low rate.
Now it is too early in the season to think this is a trend that will continue or to say exactly what may be behind it. It could simply be a matter of match-ups or cold weather affecting how he pitches. The one thing I will say though is that Strasburg’s rate of first pitch strikes is down 6% over last year, which could lead to a decrease in strikeouts. Although, that could simply be due to the small sample size.
However, it does put a spotlight on how incredible Strasburg’s strikeout rate was last season when he struck out 30.2% of the batters he faced. That 30.2% was best in the league by a full percent over Max Scherzer and five percent better than his next closest teammate Gio Gonzalez. In fact only four hitters struck out at a higher rate than Strasburg struck out opposing batters last season.
In historical context Strasburg’s 30.2 K% last season ranks nineteenth overall in the modern era for pitchers who threw more than 150 innings that year. Doing so in his age 23 season is remarkable and gives him a good chance of cracking the top ten before his career is over.
Speaking of that top ten, only three pitchers populate it. One is Kerry Wood, who made it in his rookie season in 1998. The majority of the top ten is Randy Johnson, who populates seven of the top ten spots. Two of the top three spots however belong to Pedro Martinez. The top spot being his Cy Young winning and AL MVP deserving 1999 season when he struck out 37.5% of batters faced and garnered 11.1 wins above replacement.
What is really interesting about that season is that Martinez only threw 213.1 innings. In fact in his entire career Martinez only pitched over 217 innings in two years (1997 and 1998). Those 213.1 innings pitched in 1999 were the 19th most and would have been tied for 13th most in 2012.
Much is made of the fact that Stephen Strasburg has yet to pitch into the eighth inning and certainly that is strange for a pitcher as talented as Strasburg. However, Martinez is a great example that perhaps too much is made of the number of innings pitched. Pedro Martinez was the best pitcher far and away in 1999 and he did it in only 213.1 innings. In the best stretch of his career from 1997-2005 , when his pitching WAR never fell below 5.8, Martinez averaged only 204.2 innings pitched a year. Martinez was one of the best pitchers of all-time and he did it without throwing what many would consider “ace’s innings.” Stephen Strasburg is already a great pitcher, who has put his name amongst some of the best strikeout pitchers of all-time. Whether he throws 190 or 230 innings a year, that fact will never change.