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The R League (Korean: R리그), also known as the Korean Professional Football Reserve League, is the league for reserve teams of professional football clubs in South Korea.
History
The Korean Reserve League was started in 1990 with reserve teams of five K League clubs.
It was not held for nine years after the inaugural season, but was relaunched in a new format in 2000. The participating teams were split into two or three group leagues, and high ranking teams of each league qualified for the playoffs to decide overall champions. It was renamed "R League" in 2009. Korean Police participated in the R League until 2012, although it was not a reserve team of a K League club.