A Swiss-system tournament is a non-eliminating tournament format that features a fixed number of rounds of competition, but considerably fewer than for a round-robin tournament; thus each competitor (team or individual) does not play all the other competitors. Competitors meet one-on-one in each round and are paired using a set of rules designed to ensure that each competitor plays opponents with a similar running score, but does not play the same opponent more than once. The winner is the competitor with the highest aggregate points earned in all rounds. All competitors play in each round unless there is an odd number of them.

The Swiss system is used for competitions in which there are too many entrants for a full round-robin (all-play-all) to be feasible, and eliminating any competitors before the end of the tournament is undesirable.

The Swiss system seeks to provide a clear winner with a large number of competitors and a relatively small number of rounds of competition, without a single bad result terminating participation.

The Swiss tournament format is most commonly used in games such as chess, bridge, backgammon and Scrabble. For the most part they have a far greater amount of participants than a round-robin style system could handle. One of the greatest benefits for using the Swiss-system in esports tournaments is that it gives players of all levels a fair chance to progress, whilst also providing the viewers with a better spectacle.

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