Ball Tracking Technology in Cricket Explained
How ball tracking reconstructs a delivery's path to predict whether it would have hit the stumps for LBW decisions.
What Is Ball Tracking in Cricket?
Ball tracking is the technology that reconstructs the trajectory of a cricket delivery and predicts where it would have gone had it not struck a batter, pad, or other obstruction. It is most prominently used in DRS LBW reviews to determine whether the ball would have hit the stumps, and by broadcasters to show ball-flight graphics during live coverage. The system at ICC events is called Hawk-Eye; a competing product called Virtual Eye is used in some domestic competitions.
How Ball Tracking Works
Multiple high-speed cameras (typically six or more) are positioned around the ground at different angles. Each camera records the ball's position in its frame. Software triangulates these positions across frames to build a three-dimensional representation of the ball's actual path. After the point of impact — where the ball hits the pad — the system extrapolates the predicted path using physics models of seam position, spin rate, and speed, projecting where the ball would have gone.
Accuracy and Uncertainty
Ball tracking is highly accurate for the tracked portion of the delivery (before pad impact) but is a prediction for the continuation after impact. The ICC applies a 'benefit of the doubt' rule: if the predicted impact with the stumps shows the ball clipping the edge of the stumps — partly hitting, partly missing — the original umpire's call stands. A clear prediction of 'hitting' or 'missing' fully overturns the original decision.
Other Uses of Ball Tracking
- Pitch maps — showing where each ball pitched during an over or innings
- Wagon wheels — showing where the ball travelled after being hit
- Wagon wheel analysis — overlaying multiple deliveries to show a batter's shot patterns
- Speed gun graphics — combining ball-tracking data with Doppler speed readings
- Worm charts and run-rate comparisons in limited-overs cricket
Frequently asked questions
Can ball tracking be wrong?
Yes. The prediction after impact is a model, not a measurement. Balls that hit the seam or turn sharply after impact can deviate from the predicted path. The 'Umpire's Call' zone exists specifically to account for this uncertainty.
Is Hawk-Eye the same as ball tracking?
Hawk-Eye is the most widely used brand of ball tracking technology in cricket. Ball tracking is the generic term; Hawk-Eye is the proprietary product.
Does ball tracking apply to all dismissal types?
Only LBW uses the trajectory prediction. Caught behind decisions use Hot Spot and Ultra Edge. Run-out and stumping decisions use multi-angle slow-motion replay.