有个英语句子的结构不懂，还请帮帮忙忙！

Question

Observes noted down the referees errors, of which there were 61 over the tournament .
这句话的结构看不懂额，of which 在这是干啥的，卟明白。

Answer 1

Observes noted down the referees errors, of which there were 61 over the tournament.
观察人士（或：观察员）记下这些裁判的执法过错，这些错误中有61个是在联赛中犯的。
观察人士（或：观察员）将这些裁判的执法过错记录在案，其中61个错误是在锦标赛里犯的。

拆句：
1.Observes noted down the referees errors.
2.There were 61 of the referees errors over the tournament.
先将2句合二为一，即前句为主句（主谓宾结构），后句为从句（非限制性定语从句），以whch取代从句主语的一部分the referees，且以of起头，of which引导从句

Answer 2

监控器记录了裁判的错误，其中61个超越了联赛（的规定）。
of which后置非限制性定语，即of （the referees errors） there were……。