I'm beat

宮部みゆきの "All She Was Worth"（原作 火車）が面白かったので地元の図書館にある宮部作品の英訳本は全部読みたいと思い、2番目にCrossfireを読む事にしました。話は比較的直ぐに事件現場に行きます。
They didn't look like trouble-making high school students who'd been on a spree and were bringing in one of their friends who'd drunk too much and passed out, or a motorcycle gang who'd come in to lay low and hide a member injured during a police chase. This had more of a grim, ugly look to it.
Junko rigidly observed the proceedings. It seemed that none of the four youths had noticed her at all. One of the two holding flashlights yawened loudly.
"Man, I'm beat."
"What is this place? It stinks."
"beat" を含む慣用句、口語表現は多く、これまでにこのブログでも "beats me"、"my beats"、"If that don't beat all"、"beat the hell out of"、"beat the odds"、"without missing a beat"、"beat all" を取り上げました。
今日はCrossfireに出てきた "I'm beat" です。
　
・Oxford English Dictionary: Completely exhausted.: I'm dead beat.
・Cambridge English Dictionary: extremely tired: I'm beat - I'm going to bed.