In a previous article, I looked at the average locations of R.A. Dickey's knucklers and compared them to former Red Sox knuckler Tim Wakefield. I promised repeatedly to revisit the topic, and that is what I am doing here. I used Baseball Savant to gather all the knuckleballs thrown regardless of pitcher.
This first graph shows the average locations of every pitcher that threw a knuckleball since 2008 (I took out Brad Peacock, whose curveballs were being called knuckleballs for some reason by MLBAM, and while I don't know why, and I didn't realize it until I was almost done with the article, Josh Banks and Eddie Bonine were not included in the data set).
Ryan Franklin, who only occasionally mixed in a knuckleball, threw his the lowest on average and it is not that close. Dickey has the most glove side knuckleball on average. No lefties have thrown a knuckleball in the Pitch F/X era, not even any of the position players (there have been some released on the left side of the rubber by Dickey and Wakefield, Dickey more than Wakefield, but obviously these are at parks that measure release points slightly to the left than usual or they moved around on the rubber). When looking at results of all knucklers thrown, it is really difficult to find a difference between which knucklers turned into whiffs and which ones turned into balls put in play for the three standard results
Since I looked at Wakefield and Dickey in the previous article linked to above, I'll look at two pitchers who have a significant amount of knucklers thrown in the Pitch F/X era, both of them currently in the Boston Red Sox organization. Charlie Haeger hasn't pitched in the Majors since 2010, throwing 83 innings with the Dodgers and Padres. He is currently pitching in AAA, but struggling. His knuckler (114 wRC +) was not as effective as Dickey's (85 wRC +), or Wakefield's (98 wRC +). Here were his average result locations
Steven Wright made his debut earlier this season, and while the sample size is small, no one has had a more successful knuckler according to whiff/swing % than him.
When he gets the ball glove side, he is more likely to get whiffs, but he gives up contact about equally glove side and arm side. When he keeps it arm side, it appears that hitters are less likely to swing.
I mentioned the position players who have thrown knuckleballs above (only 79 of the 20305 knucklers since 2008). The following graph shows where the position players located their knucklers on average compared to the standard pitchers
Just for fun, here are where the individual position players' knuckleballs have been thrown. Of course, probably not all of them are knuckleballs, just slow pitches that MLBAM called knuckleballs.