Analysis of knuckleball trajectories

An analysis of knuckleball trajectories is presented using data from the PITCHf/x video tracking system for pitches thrown in actual MLB games. The data reveal that, contrary to popular belief, knuckleball trajectories are as smooth as those from normal pitches. However, the data also show that the deflection of a knuckleball from a straight-line trajectory is essentially random in both magnitude and direction.