How to Run a Round-Robin Tournament

What a round-robin actually is

A round-robin is the simplest fair idea in sport: everyone plays everyone. Nobody goes home after one bad game, and the winner is whoever did best across the whole set rather than whoever got the kindest draw.

The catch is arithmetic. If 20 people all play each other, that is 190 matches. On three courts that is a very long day. This is why real events almost never run one giant round-robin.

Step 1 - split the field into pools

A pool is a small group who play each other. Instead of one enormous group, you run several small ones side by side, usually one per court.

Think of a party with 20 children and a few tables. You do not sit all 20 at one table where nobody can reach the cake. You make four tables of five.

Pools of 4 to 6 are the practical range. Fewer than four cannot fill a doubles rotation. More than six and people spend the evening watching.

Step 2 - group by standard, not by friendship

Rank everyone strongest to weakest and cut the list into your pools. Cut it where the biggest gaps in standard are, not into equal-sized groups.

Say ten players rate 9.0, 8.9, 8.8, 8.7 and then 5.0, 4.9, 4.8, 4.7, 4.6, 4.5. There is an obvious cliff after the fourth. A tidy 5-and-5 split drags one strong player down among the club players and makes both pools lopsided. Splitting 4 and 6, right on the cliff, keeps every match close.

RallyIQ does this cut for you, and it is why two friends of different standards usually land in different pools. That is the design working, not a mistake.

Step 3 - build the match schedule

Inside each pool you want three things at once: everyone plays the same number of games, nobody partners the same person twice, and sit-outs are spread out.

How that lands depends entirely on the pool size:

Five is the cleanest size. Everyone partners everyone exactly once, everyone plays four, everyone sits once. Nothing left over.

Six cannot be perfect, and that is maths rather than laziness. To have everyone partner everyone once and play equally, the sums only work when the pool size divides by four with a remainder of 0 or 1. Six leaves a remainder of 2 and would need seven and a half matches. So you choose: equal play, or complete partner rotation. Equal play is the one players actually notice, so that is the one to protect.

Step 4 - put the sitters to work

In a pool of five or six, somebody is always sitting. Give them the job of umpiring the match they are sitting out. It keeps them involved, it settles line calls before they become arguments, and it costs nothing.

A pool of four has nobody spare, so those matches self-umpire.

Decide first serve by whoever has served least so far, rather than by racquet spin. It evens out over the round and takes a decision off your plate.

Step 5 - score every match the same way

Pick one target score and use it for the whole event. First to 11, 15, 17, or a 21-point rally game are all common. What matters is that you do not mix them halfway through without a reason.

Record the full score of every match, not just the winner. An 11-9 loss and an 11-2 loss are very different pieces of information, and you cannot recover the difference later.

Step 6 - decide who won

The straightforward way is to count wins, and break ties on points scored minus points conceded.

The better way, if you have ratings, is to ask how each player did against expectation. Beating three players well above your level is a bigger achievement than beating three well below it, and a raw win count cannot see that difference. This is what RallyIQ's leaderboard is ordered by.

Read how ratings work for the reasoning behind that.