Whose statement is accepted when there is a dispute regarding the destruction or perishing of the pledged item?

Primary text

The statement of the pledgee is accepted, provided he takes an oath, concerning the destruction of the pledged item. This is because the pledgee's possession is considered a trusteeship (yad amanah), and it is difficult for him to bring forth evidence of the destruction. Therefore, his statement is accepted concerning the loss, similar to a trustee (Mudi').