Knockout stage

A single-elimination tournament—also called an Olympic system tournament, a knockout (or, knock-out), single penetration, or sudden death tournament—is a type of elimination tournament where the loser of each bracket is immediately eliminated from winning the championship or first prize in the event.

This does not always mean that the defeated competitor will not participate further in the tournament; in some such tournaments, consolation or "classification" contests are subsequently held among those already defeated to determine the awarding of lesser places, for example, a Third place playoff. Where more than two competitors can play in each match, such as in a shootout poker tournament, players are removed when they can no longer play until one player remains from the group. This player moves on to the next round.

Some competitions are held with a pure single-elimination tournament system. Others have many phases, with the last being a single-elimination final stage called playoffs.

In English, the round in which only eight competitors remain is generally called the quarterfinal round; this is followed by the semifinal round, in which only four are left, the two winners of which then meet in the final or championship round. The round before the quarterfinals is sometimes called the "round of sixteen", "Last Sixteen", or (in South Asia) "pre-quarterfinals"; in some other languages "eighth-finals" is used. Earlier rounds are typically numbered counting forwards from the first round, or by the number of remaining competitors. If some competitors get a bye, the round at which they enter may be named the "first" round, with the earlier matches called a "preliminary" round, or "play-in games".

Examples of the names given to rounds in various generic conventions and specific competitions:

4th round (Wimbledon)

Notes:

The final three rounds of the 2014 Australian Open – Women's Singles knock-out tournament:

When matches are held to determine places or prizes lower than first and second (the loser of the final-round match gaining the latter position), these typically include a match between the losers of the semifinal matches called Third place playoff, the winner therein placing third and the loser fourth. Many Olympic single-elimination tournaments feature the bronze medal match if they do not award bronze medals to both losing semifinalists. The FIFA World Cup has long featured the third place match, though the UEFA Euro has not held one since the 1980 edition.

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