Intent and Jeff Karstens

A common adage is that a pitcher needs either good stuff or location to make it in the major leagues. Jeff Karstens is not someone with good stuff. On the best of days his fastball can average a severe wind-aided 90 miles per hour. Hurricanes are uncommon in the greater Pittsburgh area so the righty settles for an average of 89 miles per hour. Karsten’s secondary offerings are superior – including a very good curveball – but the book on him is that he’s not going to get a ton of strikeouts or grounders. What he will rack up – as the adage suggests – is strikes.

Karstens is throwing 66% strikes this season, which places him in a tie with Joe Blanton and ahead of Felix Hernandez, Francisco Liriano, David Price, and a slew of pitchers with superior stuff. He’s amongst the 25 starting pitchers who throw the most strikes on a rate basis which is led by Cliff Lee (72%) and Scott Baker (70%) amongst others. This within itself isn’t too interesting or worthy of adulation because Karsten’s phobia towards throwing balls is yet to result in fantastic performances – minus one heck of a start during the 2008 season versus the Diamondbacks.

The real story to tell about Karsten’s strike rate is really about the reciprocal or his ball rate in this case. Karstens has issued five intentional walks in a little over 100 innings of work. His career total through about 217 innings entering this season was seven. That kind of really free pass rate has the tendency to creep into and distort things like strike ratio. Nobody ahead or near Karstens on the strike rate leaderboard is over more than 2% intentional balls/balls thrown, so his intentional balls are skewing his strike rate the most. What has it meant to his rate of strikes thrown?

Since we know that five intentional walks equals 20 intentional balls, then we can just subtract those balls from his total (491) and redo the division by his total pitches with those 20 pitches subtracted (1430 after the minus); giving us a real strike rate of 67%. That’s not entirely fair, though, because Karstens would have had to throw pitches versus those batters and we can’t simply pretend they never happened. What if he threw 20 pitches to each, and half were strikes – after all, 10 extra strikes instead of 10 extra balls is better than 20 balls to 0 strikes. Well, then we get a strike rate of 67% again.

67% to 66% is a minute difference; no doubt, but when we talk about strike rates or even walk rates, the amount of intentional balls and walks is often ignored.

We hoped you liked reading Intent and Jeff Karstens by R.J. Anderson!

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My understanding of the intentional walk was that only the final pitch of the plate appearance needed to be intentional. There are plenty of times where pitchers try to hit the corners or induce swinging strikes out side of the zone for the first few pitches before the manager has the catcher stand up and stick his arm out. So the assumption that 5 IBB equals 20 intentional balls might not hold water.


I think that’s partly accounted for assuming he would throw 10 strikes and 10 balls. One would think he would normally throw ~66% of those 20 pitches for strikes (since that’s his strike rate), so making it half should account for some of the unintentional balls that lead up to the intentional walk, if that makes any sense.