Circle of Death (sporting)

A circle of death tie is a tie that occurs in round robin competitions when the records of three competitors are identical, and furthermore the head-to-head record of all three is 1-1 (i.e. one win and one loss).

For example, consider a four-person round robin with teams A, B, C, and D. If A beats B, B beats C, C beats A, and A, B, and C beat D, then all three of A, B and C have a 2-1 record (two wins and one loss) overall, and a 1-1 record against each other. These teams have equivalent win-loss records, and some other form of tiebreak (such as the total number of points scored) must be applied to break the tie.

The circle of death tie can be exciting yet infuriating, since all three competitors involved are usually very close in skill, yet only one can win the tiebreak.

The name "circle of death" comes from the fact that when the head-to-head records are compared, we find that A has beaten B, B has beaten C, and C has beaten A, and so we are back where we started.

A similar tie between five or more teams that cannot be broken based solely on the teams' records is sometimes called a "death star".

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