Although the IRB (World Rugby) defines "Adult rugby" as Rugby played by teams comprising players normally 18 years of age and older", "Senior rugby" in South Africa, is defined as any form of rugby played above the u20 Age-grade level, which includes u21 age-grade level and above.
A player younger than 18 shall NOT be allowed to play u20
Keep in mind we are "working" on the year date. The player turning 18 in the year will therefor still be to young.
To play u20 the player must be 18 turning 19 in the year or already 19 years of age.
Players younger , who are selected for ELITE competition (e.g SA u/20 or Provincial u/20 and u/21, Super rugby or Currie Cup must complete a set of documents (waiver application process) and tested before practice and/or playing a match. This is ONLY for ELITE players.
Clause 3.10 referred: A player 18 years old but younger than 19 can play CLUB u/20 but NOT at a Elite u/20 or senior rugby without being identified and meeting all terms and conditions of the waiver application process.
According to the SARU Age banding "(In South Africa above the u20 Age-grade level .....)" and the Union don't have a club u/20 competition I will advice the club and coaches to get the "waiver admin process" in place before I would play an 19 year old player in Senior rugby matches just to cover myself as coach, the club and the player. See clause 6,10 and 11 as well.
This is how I understand it and I trust that I have answered the questions. I am not a legal expert so I would also like to refer you to Dr W Viljoen and/or Dr C Readhead at SARU for clearance with them