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attacking a fleeing enemy
additional blow to an already unfortunate situation; rubbing salt into a wound
敵への追い打ちをためらった。
He hesitated to press the attack on the fleeing enemy.
不運続きにさらに追い打ちがかかった。
More bad luck kept piling on top of everything else.
崩れかけた相手に追い打ちをかけるような発言をした。
He made remarks that were like attacking an already-weakened opponent.