Of course, the best referee won't cave, no matter what. For that reason, it's best to pick someone whom you trust but aren't too close to.

当然了，如论发生什么事，最好的见证人绝不会心软。所以，最好是选择那些你信任，但是又不是很亲近的人作为见证人。

youdao

"To become a referee, the Madrid Football Federation makes us take a course as well as two classes with a psychologist, because it is common knowledge that you'll be verbally abused, " he said.

CNN: Soccer violence: Referees under siege