If a yokozuna (grand champion) loses to a lower ranked wrestler in a Grand Sumo tournament, the audience members sitting in the ringside seats throw their zabuton towards the ring to express disappointment with the yokozuna and praise the wrestler who won.
大相撲で横綱が格下の力士に負けたときに、横綱への落胆と勝った力士への称賛の意味を込めて、桟敷席の観客が座布団を土俵に向かって投げる行為。