Four tables, four systems of measurement: when a billiards data sheet forgets to name the discipline

On 10 March 2026, at the Guild Hall in Preston, Ronnie O'Sullivan completed the one thousandth century break of his professional career in the final of the Players Championship against Neil Robertson. The arena stood before the last ball had settled. I was in the fourth row back from the entrance, notebook open, and I wrote exactly one line: this milestone exists only on a table twelve feet long.

A century is a run past 100 points in a single visit, on a 12-foot table, with fifteen reds racked in a triangle and six colours. The number is a product of a table structure, a rulebook and a racking convention. It does not measure billiards. It measures snooker.

This season a data sheet landed on my desk with exactly that column heading. Beneath it sat the figures from a Chinese 8-ball leg staged in Yushan, Jiangxi province. The column was empty. Not because nobody had entered the data. It was empty because on a Chinese 8-ball table — 9 feet, 2¼-inch balls, pocket jaws rounded and tightened in the snooker style — the concept of a century does not exist.

A blank in the right place is worth more than a handsome number. And that blank tells almost the whole story of how billiards is being analysed today.

Four tables, four rulebooks, four ways of counting

Four professional cue sports run in parallel across the same news page, with four systems of measurement that cannot be converted into one another. Snooker uses a table 3569 mm by 1778 mm, balls of 52.5 mm, fifteen reds and six colours, and rounded pocket jaws. Pool — nine-ball and American eight-ball — uses a 9-foot table, 57.15 mm balls, wider and shallower pockets. Chinese 8-ball takes the 9-foot pool frame but tightens the jaws in the snooker manner and keeps the 57.15 mm ball: a hybrid built for television. Three-cushion carom uses a 2.84 by 1.42 m table with no pockets at all and three balls of 61.5 mm.

The vocabulary splits four ways as well. Snooker says break-building, safety, laying a snooker, free ball, miss rule. Pool says break shot, push-out, break-and-run, calling ball and pocket. Carom says average per innings, series, innings, a 40-point set. Mix two of those vocabularies in one article and the prose still reads smoothly, but the first line is already wrong.

Vietnamese readers receive all four feeds at once, which is why this trap bites harder here than in a single-discipline market. On 10 September 2026, in Ankara, Bao Phuong Vinh beat Tran Quyet Chien in an all-Vietnamese final to win the world three-cushion championship. Tran Quyet Chien has held the world number one ranking in that discipline. In the same week, the international wire belonged to O'Sullivan and the snooker tour, while the money flowed to Yushan.

Three sources, three systems of measurement, one front page. An editor under output pressure will very easily label all three as billiards and reach for a single ruler.

I do not watch a match from the stands. I count the visits a cueist is forced to sit through. But to count, I have to know which table I am counting on.

In 2026, building a six-signal coding system for Liverpool's pressing game, I learned a principle I have since reused almost intact for billiards: to code anything you need a single convention sheet, and the sheet has to state what it applies to. Without that sheet, every number is noise with formatting.

In billiards, that convention sheet begins with the name of the discipline. Every comparison sits behind it, and every comparison that skips it is void.

An empty cell is not a data-entry error

Centuries and 147s exist only in snooker. A maximum is the highest score available in one perfect visit on a snooker table, with fifteen reds, fifteen blacks and six colours. In pool, the functional equivalent is the break-and-run: split the rack, then clear the table in a single visit without handing it back. The unit is different — racks instead of points.

Carom uses a third denominator. In each visit a player keeps shooting until he misses; then the opponent takes the table. So the king metric in carom is average points per innings, alongside the series — the longest run within one visit. At world level a player averages around 1.8 points per innings. Set that 1.8 beside a snooker player with fifteen maximums and conclude that one is better than the other, and you have divided by the wrong denominator. Do not ask me how good that cueist is. Ask me how many points per innings he scored in the third set.

Push-out exists only in nine-ball. It is the optional shot immediately after the break, used to leave an awkward layout for the opponent. Snooker does not have it. Carom does not have it. An analysis that explains a snooker shot with push-out is describing a stroke that does not exist.

The events of 5 May 2026 show how the snooker measurement system operates. Zhao Xintong beat Mark Williams 18-12 at the Crucible to become the first Asian world champion, returning from a 20-month suspension. That route ran through best-of-19, best-of-25, best-of-33 and best-of-35 formats. It was a test of technical endurance over long distance, where break-building and the ability to hold position for hours decide the outcome.

If Zhao plays a Chinese 8-ball leg tomorrow, his century count does not travel with him. His positional control travels partly. What travels most is composure in deciders — and composure has no unit of measurement.

Format is the decisive variable

In every cue sport, format is the strongest variable, stronger than form and stronger than head-to-head history. A best-of-33 event filters for true strength. A race-to-4 compresses the skill gap almost to zero and turns every seed into a soft target.

Snooker supplies the most extreme example in all of cue sport: the Shoot Out, one frame, a ten-second shot clock, and a ranking event since 2026. There, a top-16 player can leave the tournament in ten minutes, and frequently does. The ranking list records that result like any other.

Pool has its own variable: alternate break or winner break. Under winner-break in a race-to-7, a player in stroke can run four racks while the opponent never touches the table. Switch to alternate break, same two players, and the scoreline changes entirely. A line reading A beat B 7-3 says nothing unless it names the break rule.

Carom is played in sets, usually to 40, best of three. A player who loses the first set 40-12 can still take the title, because the match average is decoration. Carom scoreboards are read by set, not by total points.

The consequence for readers: a result carries only as much evidential weight as the format that produced it. Before asking who won, ask over how many frames, under which break rule, and with or without a clock.

Which ranking?

Snooker ranks by prize money rolling over two seasons. A big result counts for 24 months and then evaporates. That mechanism creates a cliff at number 64: below it a player loses the professional tour card, and losing the card means losing most of his income.

Pool ranks through the WPA system and individual promoters. Carom ranks on UMB points. Chinese 8-ball runs on its own commercial money list, where appearance fees sometimes exceed the winner's cheque at a small snooker ranking event.

Four systems, four definitions of world top ten. A line that says the world number ten without naming the system is a sentence without a reference.

For those who work in the sport, this matters more than it looks. The number-64 cliff explains why a snooker player ranked 50th accepts a Chinese 8-ball booking in Asia during an off week: that is an accounting decision, not a sporting one. It also explains why a miss in qualifying weighs more than a miss in the semi-final of an invitational.

Who holds jurisdiction

Authority splits by discipline too. Snooker has the WPBSA for discipline and WST for commercial operations. Pool is fragmented between the WPA and event promoters. Carom sits under UMB. Chinese 8-ball is coordinated by the domestic association together with commercial operators.

In October 2026 the WPBSA announced sanctions against ten Chinese players over betting-rule breaches. Liang Wenbo and Li Hang were banned for life. Yan Bingtao was banned for five years. One body, one rulebook, one sanction ladder, applied to every member of the same system.

Earlier, in 2026, John Higgins was suspended for six months and fined 75,000 pounds for failing to report an approach, after being cleared of match-fixing. Two cases thirteen years apart, the same body, the same logic: investigate, conclude, publish, enforce.

In a sport with four different bodies, the same conduct can draw four different sanctions, or none at all. So when reading an integrity story in billiards, the first thing to establish is who is speaking — and which discipline they hold authority over.

The blind spot is the label

The analytical industry believes the problem is a shortage of data and the answer is more of it: more cameras, more sensors, more dashboards. I read it the other way. In billiards there is already too much data. What is missing is the label stating which table the number belongs to.

Say the opposite — that the measurement systems are convertible — and that century column would have values in it, and I would have nothing to write. The column is empty. The counter-hypothesis collapses on its own.

The second blind spot is the belief that short formats are a television matter. They are not. Short formats are quietly erasing a type of cueist: the specialist defender, the player who wins by pushing opponents into positions they cannot play from. In snooker that is the man laying snookers and waiting for the error. In carom it is the man pinning balls to the cushion and forcing a risky stroke. Short formats do not reward patience; they reward the finishing shot.

The result is a silent homogenisation. Every young cueist is taught to play fast, hit hard, close early. The defensive craftsman is filed as slow, and slow is filed as finished. Ten years from now, if every event is a race-to-5, we will have a generation that does not know how to win a frame without a big break.

The third blind spot is the calendar. A professional snooker player now has more than twenty ranking events a season, plus invitationals, plus commercial legs in Asia, plus occasional appearances in other disciplines. Touch is not a thing you maintain at two events a week. No coaching team keeps a player's feel alive across four time zones in ten days. When a player misses in the first round, my first question is how many hours he slept, not which shot he practised.

Next time, ask about the table first

When the arena goes quiet, I hear very clearly the sound of a measurement system cracking because it refuses to name itself.

Preston 2026 taught me one thing: data does not win frames, it only wins before the cue touches the ball.

At fifty-nine I still believe something I mocked at twenty: a blank in the right place is more trustworthy than a beautiful number.

Next season, when a data sheet appears, the first questions put to it are these: on which table was this counted, under which rulebook, in which format, and recognised by which body. Four questions, asked before the number is read. And one more for Vietnamese billiards: which system will we choose to measure ourselves by — the system of the man who won a world three-cushion title, or the system of a spreadsheet imported from somewhere else?