Tournament


A tournament is a competition involving at least three competitors, all participating in a sport or game. More specifically, the term may be used in either of two distinct senses:
  1. A competition involving a number of matches, each involving a subset of the competitors, with the overall tournament winner determined based on the combined results of these individual matches.
  2. One or more competitions held at a single venue and concentrated into a relatively short time interval.
The first sense is common in sports and games where each match must involve a small number of competitors, often precisely two, as in most competitive team sports, racket sports, combat sports, card games, and board games. Such tournaments allow large numbers to compete against each other in spite of the restriction on numbers in a single match. All golf tournaments meet the second definition, but while match play tournaments also meet the first, stroke play tournaments do not, since there are no distinct matches within such tournaments. In contrast, association football leagues like the Premier League hold tournaments only in the first sense, as matches are spread across many venues over an extended period of time. Many tournaments meet both definitions; for example, the Wimbledon tennis championship.
The term match may be used in multiple ways. Most commonly, it is used to refer to a tournament-match, the results of which are used in some way to determine the winner of a tournament. It can also refer to a game-match, one or more of which are used to determine the result of a single tournament-match. If necessary, one or more tiebreak-matches may also take place. Sometimes there are further layers, such as in tennis, where a tie can consist of sets which themselves consist of games. For example, in the Major League Baseball postseason, a series between two teams involves up to five or seven games between the two teams, with the team that reaches three or four wins winning the series. In the Davis Cup tennis tournament, a tie between two nations involves five rubbers between the nations' players. The team that wins the most rubbers wins the tie. In the later rounds of UEFA Champions League, each fixture is played over two legs. The scores of each leg are added, and the team with the higher aggregate score wins the fixture, with extra time, and if necessary, a penalty shoot-out used if the scores are level after both matches conclude. In this case, the first tiebreak-match is extra time and the second tiebreak-match is a penalty shoot-out.

Knockout tournaments

A knockout tournament or elimination tournament is divided into successive rounds; each competitor plays in at least one fixture per round. The top-ranked competitors in each fixture progress to the next round. As rounds progress, the number of competitors and fixtures decreases. The final round, usually known as the final or cup final, consists of just one fixture; the winner of which is the overall champion.
In a single-elimination tournament, only the top-ranked competitors in a fixture progress; in 2-competitor games, only the winner progresses. All other competitors are eliminated. This ensures a winner is decided with the minimum number of fixtures. However, most competitors will be eliminated after relatively few matches; a single bad or unlucky performance can nullify many preceding excellent ones.
A double-elimination tournament may be used in 2-competitor games to allow each competitor a single loss without being eliminated from the tournament. All losers from the main bracket enter a losers' bracket, the winner of which plays off against the main bracket's winner.
A triple-elimination tournament allows a competitor to lose two games and creates a third bracket or fourth bracket which are usually followed by a playoff. It is commonly used in curling tournaments.
Some elimination tournaments are in a best-of-n series, requiring a competitor to lose a majority of n games before being eliminated.
Some formats use a repechage, allowing losers to play extra rounds before re-entering the main competition in a later round. Rowing regattas often have repechage rounds for the "fastest loser" from the heats. The winners of these progress, but are at a disadvantage in later rounds owing to the extra effort expended during the repechage.
A family of tournament systems that grew from a system devised for the Victorian Football League, the historic predecessor to the Australian Football League, allow the teams with the best record before the playoffs to lose a game without being eliminated, whereas lesser qualifiers are not. Several of the most prominent leagues in Australia use such a system, such as the AFL and the National Rugby League in rugby league. The A-League of association football also used such a system through its 2011–12 season, but now uses a pure knockout playoff. Similar systems are used in cricket's Indian Premier League and most curling tournaments, and were also used by the Super League of European rugby league before being scrapped after the 2014 season.
In athletics meetings, fastest losers may progress in a running event held over several rounds; e.g. the qualifiers for a later round might be the first 4 from each of 6 heats, plus the 8 fastest losers from among the remaining runners.
An extreme form of the knockout tournament is the stepladder format where the strongest team is assured of a berth at the final round while the next strongest teams are given byes according to their strength/seeds; for example, in a four team tournament, the fourth and third seed figure in the first round, then the winner goes to the semifinals against the second seed, while the survivor faces the first seed at the final. Four American sports organizations either currently use this format, or have in the past:
  • Since the mid-1960s, most ten-pin bowling events use a stepladder final, usually involving five bowlers.
  • Two U.S. college conferences operate a tournament format in basketball that combines two stepladder tournaments into one—that is, both halves of the bracket are organized as stepladder tournaments. When eight teams are involved in the tournament, the bottom four teams play in the first round; the survivors will face the #3 and #4 seeds, and the winners of those matches take on the top two seeds in the semifinals. This format was used by the West Coast Conference for its men's and women's tournaments from 2003 through 2013, and has been used by the Ohio Valley Conference for men since 2011 and women from 2011 through 2014. From 2019 forward, the WCC tournaments will return to the aforementioned format, but add an extra round so that all 10 current conference members will participate.
  • In the Philippines, the UAAP Basketball Championship and the NCAA Basketball Championship both use the stepladder format if a team wins all elimination round games. This format has been adopted to other sports in both leagues, and to other leagues. If no team wins all elimination round games, the playoffs remain in the usual two-round playoff format.
  • The now-defunct Women's Professional Soccer used this format in all of its three seasons of existence. For an example of its playoff system, see 2009 Women's Professional Soccer Playoffs.

    Group tournaments

A group tournament, league, division or conference involves all competitors playing a number of fixtures. Points are awarded for each fixture, with competitors ranked based either on total number of points or average points per fixture. Usually each competitor plays an equal number of fixtures, in which case rankings by total points and by average points are equivalent. The English County Championship in cricket did not require an equal number of matches prior to 1963.
In a round-robin tournament, each competitor plays all the others an equal number of times. This is often seen as producing the most reliable rankings; however, it may require an unfeasibly large number of rounds for large numbers of competitors. A Swiss-system tournament attempts to determine a winner with a reduced number of rounds. Fixtures are scheduled one round at a time and depending on the results of the previous one, with competitors playing against those with a similar record in previous rounds of the tournament. This allows the top competitors to be determined more quickly than a round-robin, though the middle rankings are unreliable.
For clarification, this means in hypothesis UEFA adopts a Swiss System for UEFA Champions League, the second matchday in the first stage would depend on the results of the first matchday of the same stage, the third matchday would depend on the results of both the first and the second matchday, and so on, in contrast to the predetermination of all Groups Stage fixtures upon the initial draw.
Another tournament system that attempts to reduce the number of fixtures per competitor is the Pot System. Under that system, competitors are divided to different "pots" based on predetermined ranking and are drawn to play one rival from each pot, including their own pot. For example, in a 36-team World Cup, teams would be divided into 3 pots, with each team playing 3 matches - one against a Pot A team, one against Pot B team, and one against a team from Pot C. All teams are then placed in one general standing the defines qualification to the following stage.
There may be other considerations besides reliability of rankings. In some professional team sports, weaker teams are given an easier slate of fixtures as a form of handicapping. Sometimes schedules are weighted in favour of local derbies or other traditional rivalries. For example, NFL teams play two games against each of the other three teams in their division, one game against six of the other twelve teams in their conference, and one game against five of the sixteen teams in the other conference.
American sports are also unusual in providing fixtures between competitors who are, for ranking purposes, in different groups. Another, systematic, example of this was the 2006 Women's Rugby World Cup: each of the teams in Group A played each of the teams in Group B, with the groups ranked separately based on the results. An elaboration of this system is the Mitchell movement in duplicate bridge, discussed [|below], where north–south pairs play east–west pairs.
In 2-competitor games where ties are rare or impossible, competitors are typically ranked by number of wins, with ties counting half; each competitors' listings are usually ordered Wins–Losses. Where ties are more common, this may be 2 points for a win and 1 for a tie, which is mathematically equivalent but avoids having too many half-points in the listings, or 3 points for a win and 1 for a tie, which de-emphasizes ties in favor of playing to a decisive result. These are usually ordered Wins–Ties–Losses. If there are more than two competitors per fixture, points may be ordinal.