The Three and a Half Centimetres of Umpire's Call: How Ball Tracking Quietly Decides Cricket's Integrity

The clock read 10:47 pm. On the third umpire's monitor at Mirpur's Sher-e-Bangla Stadium, the last frame of ball tracking froze, and the whole gallery exhaled at once—some in despair, some in relief. The batter had reviewed, the captain had raised a finger, and on the big screen the green tracking line was creeping into view. It grazed the side of the stump and stopped, and two small words appeared beneath it—Umpire's Call. The decision stood. The on-field umpire's out, the TV umpire's out, the scoreboard's out. One part of the crowd whistled; another could not understand what it had just seen.

Since that night I have wondered many times what we are actually arguing about. We argue about whether the batter was out. But the technology no longer lets us ask that question. It puts a completely different one in front of us—what percentage chance did the ball have of hitting the stumps, and how much of that probability counts as certain. The answer to that single question settles a match, a series, sometimes the turn of a career.

The Decision Review System arrived with a promise to reduce error. It began in limited form in the 2026 Sri Lanka–India series, then expanded across all formats after the 2026 World Cup. The core philosophy is simple: the on-field umpire's decision is final, but a clear error can be overturned. The emphasis must fall on the word clear, because that one adjective holds up the entire DRS architecture.

The law needs to be understood in one sentence. In an LBW review, three things are checked: first, whether the ball pitched in line with the stumps; second, whether the batter hit the ball before it struck the pad, that is, impact in line; third, whether the ball would have hit the stumps. The first two can be measured fairly reliably by hawk-eye. But the third—ball tracking—creates the most argument.

How does ball tracking work? Cameras follow the ball's path over several metres of the pitch, marking its position in every frame, then project the post-bounce trajectory through a mathematical model and draw it to the stumps. That projection is never one hundred percent certain—it is a calculation of probability. To manage this uncertainty, the ICC built a device called Umpire's Call.

In plain terms: if less than half of the projected ball hits the stumps, it is Umpire's Call—the on-field decision stands. Only if more than half is certain to hit the stumps is a batter given out. The technology does not decide; it only decides who gets the right to decide.

Now consider how much room that half-ball really is. A cricket ball is roughly seven centimetres in diameter. So this tolerance band is only about three and a half centimetres wide. If the tracking model shifts by two or three centimetres—not technically unusual—the decision jumps from one side to the other. I have spent hours stepping through frames on screen, and two different camera angles of the same delivery sometimes show slightly different tracking. Fourteen frames can overturn a decade of habit—and that is equally true in cricket.

So when the on-field umpire gives it out and the tracking shows Umpire's Call, we are not watching the decisions of two umpires. We are watching a probability boundary set by a piece of software. The question is not the umpire's conscience; it is the model's tolerance.

A comparison helps here, even though cricket and football differ. VAR entered its first World Cup in 2026. On 16 June 2026 in Sochi, the France–Australia match produced the first VAR-awarded penalty in World Cup history—Antoine Griezmann, 58th minute, and the review ran three minutes and twenty-six seconds. That day I sat on a Dhaka studio panel counting the clock, while the other panellists argued about justice. I was only noticing that the technology took three minutes and twenty-six seconds to decide, while the game's tempo and the players' morale changed within those three minutes.

Cricket's DRS faces the same problem, with a different outcome. VAR stops play and restores a decision; DRS stops play and either upholds or overturns it. This is where the economics of Umpire's Call is created. Every review is an asset—you hold a limited number, and losing one means it never returns.

The strangest aspect of Umpire's Call is this: you lose, yet the on-field umpire is not proven wrong either. The batter feels cheated, the umpire feels vindicated, and the technology quietly stays silent after half-truths to both sides. This three-way uncertainty is the heaviest psychological burden for teams like Bangladesh. When the Mirpur gallery chants cheating, it is not blaming the umpire; it is blaming that half-ball calculation—which is invisible to its eyes.

Look at the review arithmetic more closely. A Test side gets two reviews per innings, limited-overs cricket usually one or two. A successful review returns; a failed one is lost. The calculation is like a gamble—how much risk to take, and when. If a captain burns a review in the first over, he has nothing left for a big decision late on. I have seen across many matches that players keep this arithmetic in their heads but will not admit it on camera.

One more thing is usually skipped—Umpire's Call does not protect the technology, it limits it. If every faint touch were given out, batting would never feel normal. This three-and-a-half-centimetre tolerance is therefore a kind of balance—one that saves the game from the excessive power of technology.

A factual point belongs here, one that rarely enters the debate: front-foot no-ball and LBW tracking are two different technologies, yet both rest on frame-by-frame analysis of the ball's path. When the third umpire zooms into the no-ball frame, he checks whether the back of the foot is inside the line. That too is literally a game of centimetres and frames. Ball tracking and no-ball technology are two children of the same logic—both teach us that many cricket decisions are not about the eye but about calibration.

Bangladesh cricket has argued over many such decisions—some dramatic dismissals of Mushfiqur Rahim, an LBW of Shakib Al Hasan, a slow-motion catch review of Litton Das. But at depth, the arguments are about the transparency of the protocol, not individual decisions. Much of what we call an umpire's error is really the grey edge of a protocol.

Now an uncomfortable thing must be said. DRS critics say the technology destroys the game's naturalness and erodes the umpire's authority. DRS supporters say technology reduces error. Both sides skip one thing—technology here does not reduce error, it distributes the blame for error. Once the decision was the umpire's alone; now it is shared among the umpire, the tracking model and the protocol. When responsibility is divided, accountability is divided too, and exactly that accountability gap is filled by the anger of the fans.

And one more thing is worth keeping in mind: right now almost every Test-playing nation is unhappy with Umpire's Call, yet no one agrees to abolish it—because every alternative would leave some side more dissatisfied. This is no victory of technology; it is the quiet border of an impossible compromise. — Root: INTP / Referee.

In the cricket ahead, the question will not be whether the batter was out. The question will be: will you show me that half-ball calculation of ball tracking on the TV screen? The day the protocol starts displaying its own uncertainty in public, the whistling in the gallery may stop. A rule is a hypothesis until the replay tests it. Umpire's Call is still waiting for that test.