silent soccer

(名詞) 無聲足球:一種不許觀眾叫喊、歡呼,也不許教練站在場外的足球賽。亦叫做 silent Saturday (or Sunday) soccer, silent sidelines

I just got back from my nine-year-old daughter's house league soccer game. Her team won — 3 to 1. But we parents were to keep our enthusiasm to polite clapping. This is "silent soccer" week — no coaxing, cheering or sideline coaching from coaches allowed.
—Jacqueline, "No cheers for silent soccer," Today's Parent, July 27, 2011

No yells, screams or even cheers are to be heard from the sidelines and benches at house-league soccer games in Aurora, Ont., this week.

Instead, only clapping is allowed.

So-called silent soccer has been embraced by the Aurora Youth Soccer house league and has taken hold with a handful of clubs and leagues in Canada and other countries.
—Carys Mills, "Silent running: Soccer league tells parents to pipe down," The Globe and mail, July 27, 2011