“Keep your eye on the ball” is a mantra I’ve heard applied to several sports: baseball, for hitting, football, for receiving, and golf, for teeing it up. It wasn’t surprising to me when I read recently that cricketers also use this platitude to teach batsmen how to hit effectively.
The sum total of my experience with cricket is watching multi-ethic games in Van Cortland Park through our Bronx apartment window while Greta and I were finishing graduate school about 12 years ago. I didn’t pick up on many of the rules, but I was stunned to see that cricketers, unlike baseball players, actually had to hit balls on the bounce.
A study by Michael Land and Peter McLeod takes a close look at exactly how cricket batsmen are able to follow the ball closely enough to accurately hit it. The authors point out that a fast ball takes just 600 milliseconds to reach the batsman. The fastest batsmen can adjust their shots in 200 milliseconds, which also corresponds to the time from the bounce to reaching the bat on a “good ball” — the ideal bounce point. If the ball bounces closer to the batsman, it’s relatively easy to hit because the batsman need not react to the bounce. If the ball bounces farther from the batsmen, he has time to react, even to an odd bounce.
What Land and McLeod wanted to know is whether good batsmen actually followed the “keep your eye on the ball” advice. They monitored the play of three batsmen: one professional, one a good amateur, and one a poor amateur, to see if they could identify consistent patterns in their batting behavior.
Players faced an automated bowling machine (“bowling” is the cricket term for delivering the ball to the batsman [see Chris’s comment below for an explanation of the process]; the person doing the bowling is the bowler). Each player was equipped with a headset that videotaped in the precise direction the player’s head was facing. A second videocamera monitored the player’s eye movements. Take a look at this sample of the results:
These six frames of the good amateur’s view, taken at intervals of about 100 milliseconds, show both the path of the ball and the orientation of the fovea — the tiny area of our visual system that can accurately focus on details. I’ve enhanced the image to make it easier to see what’s going on: the yellow dot represents the fovea, while the red dot is the ball.
Notice that in frame 1, the player is focused right on the ball. In frame 2, when the ball has just been bowled, again the fovea is close to the ball. But in frame three, the fovea quickly moves ahead of the path of the ball — approximately to its bounce point. In frame 4, where the ball bounces, the fovea and ball again overlap. But by frame 6, the fovea again moves away from the ball — remember, by this point, it’s impossible for the batsman to react to the ball’s movement.
Land and McLeod plotted the angle of the ball and fovea relative to the head position for each player, as well as for each type of pitch. A typical plot looked like this:
These plots show that each player used essentially the same strategy: they followed the ball closely for the first 200 or so milliseconds. Then they quickly shifted their view to the predicted bounce point and waited for the ball. When the ball bounced, they maintained focus on it for as long as possible, even though at this point it was no longer possible to react to the ball’s movement. The main difference between the better and worse players was how closely they followed the ball’s trajectory: the professional followed the ball most closely, both at the beginning and the end of its flight.
How did this translate into game-time performance? The professional and the talented amateur were able to attack balls that bounced either earlier or later than the ideal bounce point. The less talented amateur was forced to make defensive swings on all but the early-bouncing balls (“short pitches”). Better players were able to make good swings more often than poorer players.
What information were the batsmen using to make their swings? Based on the data they gathered, Land and McLeod argued that batsmen rely primarily on the time it takes from the ball to leave the bowlers hand and when it hits the ground: this, combined with the location of the bounce, can give a good judgment of the ball’s speed, allowing them to predict the height and time it will reach their bat. Other factors, such as binocular disparity (triangulating the distance to the ball based on the different perspectives offered by each eye), were determined to be too difficult to calculate given the distance to the ball and amount of information available.
Now, if only Land and McLeod could explain the meaning and origin of the phrase “sticky wicket,” and why cricket only has two bases, I think I might begin to understand how this elusive game is played.
Land, M.F., & McLeod, P. (2000). From eye movements to actions: How batsmen hit the ball. Nature Neuroscience, 3(12), 1340-1345.