Statistically Speaking: Winning with an 89-mph fastball: an analysis of Brian Bannister (Part 1)

The latest work from Mike Fast…

Bannister claimed he’d been able to get batters to put the ball in play 155 times with a 0-2 or 1-2 count versus 78 times at 2-0 or 2-1. In 2007, batters put the ball in play against Bannister 78 times at 0-2 and 1-2 versus 61 times at 2-0 or 2-1. The numbers he quoted were for his career, so to check them, we need to add in his 2006 numbers, 19 and 17 respectively, to get a total of 97 career balls in play at 0-2 or 1-2 and 78 career balls in play at 2-0 or 2-1. The second number matches what Bannister said, but the first number isn’t even close. Did Bannister leave out a count? I can’t find any other combination of counts that adds up to the numbers Bannister said. You can look for yourself.

Inconsistencies in Bannister’s arithmetic aside, the main thing to note is that he did not induce balls in play in advantageous counts more often than average. He comes out at slightly less than a one-run disadvantage overall, including, notably, a 1.6-run disadvantage at 0-2. When looking at his run values for balls in play, we need to remember that small sample size affects the reliability of these numbers. You might be able to chalk most of this effect up to chance. In any case, Bannister is certainly not gaining any advantage here.

Where does that leave us? Are we left knowing nothing more than when we started other than that the reasons Bannister offered for his BABIP performance don’t hold water? In Part 2, we’ll move on to the PITCHf/x data set and see if learning more about his arsenal can help us answer the BABIP question.