Relegation and promotion

In sports leagues, promotion and relegation is a process where teams are transferred between two divisions based on their performance for the completed season. The best-ranked team(s) in the lower division are promoted to the higher division for the next season, and the worst-ranked team(s) in the higher division are relegated to the lower division for the next season. In some leagues, playoffs or qualifying rounds are also used to determine rankings. This process can continue through several levels of divisions, with teams being exchanged between levels 1 and 2, levels 2 and 3, levels 3 and 4, and so on. During the season, teams that are high enough in the league table that they would qualify for promotion are sometimes said to be in the promotion zone, and those at the bottom are in the relegation zone (or, colloquially, the drop zone or facing the drop).

An alternate system of league organisation which is used primarily in the US, Canada and Australia is a closed model which always has the same teams playing, with occasional admission of expansion teams and relocation of existing teams, and with no team movement between the major league and minor leagues.

The number of teams exchanged between the divisions is almost always identical. Exceptions occur when the higher division wishes to change the size of its membership, or has lost one or more of its clubs (to financial insolvency or expulsion, for example) and wishes to restore its previous membership size, in which case fewer teams may be relegated from that division, or (less often) more teams will accepted for promotion from the division below. Such variations will almost inevitably cause a "knock-on" effect through the lower divisions. For example, in 1995 the Premier League voted to reduce its numbers by two and achieved the desired change by relegating four teams instead of the usual three, whilst allowing only two promotions from Football League Division One. Even in the absence of such extraordinary circumstances, the pyramid-like nature of most European football league systems can still create knock-on effects at the regional level. For example, in a higher league with a large geographical footprint and multiple feeder leagues each representing distinct geographical regions, should most or all of the relegated teams in the higher division come from one particular region then the number of teams to be promoted and/or relegated from each of the feeder leagues may have to be adjusted and/or one or more non-promoted and non-relegated team(s) playing near the "boundary" between the feeder leagues may have to transfer from one feeder league to another to maintain numerical balance.

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Wikipedia