last-ditch
adjective uk/ˌlɑːstˈdɪtʃ/ us/ˌlæstˈdɪtʃ/ (also last-gasp)
last-ditch attempt/effort 最后一招，最后一根救命稻草;孤注一掷
an effort or attempt that is made at the end of a series of failures to solve a problem, and is not expected to succeed
He resigned in a last-ditch attempt to save his party from electoral defeat. 为了避免他所在的政党在大选中失利，他使出了最后一招——辞去了领导职务。