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to one's regret; regrettably; to one's chagrin
惜しくも、彼は敗れた。
Regrettably, he lost.
我がチームは惜しくも優勝を逃した。
Our team regrettably missed out on the championship.
彼の選手生活は惜しくも無冠で終わった。
Regrettably, his athletic career ended without a championship.