Sportdigital Reserve league and Elite league In early years the reserve league was open to all of the reserve teams from the Chinese Super League, China League One, and China League Two clubs. In 2011, the lower leagues started their own reserve league. The CSL reserve league strictly allows CSL clubs to compete, it is played at the next day of the regular league, also in home and away format, since 2018, the reserve league is held in the same venue of the regular league. From 2014 to 2017, an elite league was held under the reserve league, restricted to players between 17 and 19 years old. Youth development and Youth super league Since the inception of the CSL, the CFA has required all of its clubs to operate youth development, yet it was not a strict criteria until 2018. In the CSL club criteria created in 2017, clubs who could not meet the youth development programme criteria will be relegated to lower leagues. According to the CSL club criteria, the youth teams of CSL clubs must have their own training center, coaching staff, and medical group, and a minimum of 15% of club budgets must be invested into youth programmes. CSL clubs are required to have 5 youth level teams at ages U19, U17, U15, U14 and U13. Clubs must have youth academies and introduce grassroots football plans to cooperate with local football associations, school and social corporations. In 2017 the Youth League system was officially rebranded as Youth Super League. YSL is open to all the youth teams of all professional clubs, selected football academies and local FA training teams in China. Since 2018 the U19 Youth Super league is played with two groups of 18, a total of 36 clubs. Clubs plays home and away season with promotion and relegation introduced. The U17 and U15 Youth Super Leagues play in six regional leagues with 76 and 77 teams respectively. The U14 and U13 Youth Super leagues play in five regional leagues with 40 and 45 teams respectively. Besides the Youth Super League, there are also other tournaments for youth teams across China, including Youth Championship plays in pre-season, Youth FA cup runs during the Youth Super League fixture, and Youth Champions Cup plays in off-season. See also Football in China Chinese Football Association Chinese football champions Chinese football records Chinese FA Cup Chinese FA Super Cup Chinese