When watching a high level wrestling match you may come across a curious tradition where a wrestler, after a match, takes off their shoes and leave on the mat. It is a tradition in reference to a saying all wrestlers know and use:
“Leave it all on the mat.”
It is a sign of the wretsler retiring from the sport. It is usually done at a very high level, either collegiate, international or Olympic level.
The equivalent in BJJ would be to leave your belt on the mat or in MMA to leave your gloves, just like renato Babalu Sobral did.
This video covers the subject: