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being a match for a thousand; being a mighty warrior (combatant, player)
彼は一騎当千の武将として恐れられた。
He was feared as a warrior worth a thousand soldiers.
一騎当千の活躍で試合に勝利した。
With a performance worth a thousand warriors, they won the game.
あの選手は一騎当千の強さを持つ。
That player has the strength of a thousand warriors.