a last-ditch stand/attempt/effort

last-ditch attempt

A final effort or attempt to solve a problem or avoid failure or defeat, especially after a series of failures or setbacks. The home team is mounting one last-ditch attempt in the final seconds of the game to try to force an overtime showdown. In a last-ditch attempt to avoid a government shutdown, congress has pushed forward a new spending bill.
See also: attempt

last-ditch effort

A final effort or attempt to solve a problem or avoid failure or defeat, especially after a series of failures or setbacks. The home team is mounting one last-ditch effort in the final seconds of the game to try to force an overtime showdown. In a last-ditch effort to avoid a government shutdown, congress has pushed forward a new spending bill meant to plug the debt ceiling for another year.
See also: effort
Farlex Dictionary of Idioms.

*last-ditch effort

Fig. a final effort; the last possible attempt. (*Typically: be ~; have ~; make ~.) I made one last-ditch effort to get her to stay. It was a last-ditch effort. I didn't expect it to work.
See also: effort
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

last-ditch effort

A desperate final attempt, as in We're making a last-ditch effort to finish on time. This expression alludes to the military sense of last ditch, "the last line of defense." Its figurative use dates from the early 1800s.
See also: effort
The American Heritage® Dictionary of Idioms by Christine Ammer.

a ˌlast-ditch ˈstand/atˈtempt/ˈeffort

a final attempt to avoid defeat: They are making a last-ditch stand to save the company. This is a last-ditch attempt to stop the strike. Ditch in this idiom refers to a long channel built to defend an area against attack.
See also: attempt, effort, stand
Farlex Partner Idioms Dictionary
See also:
  • attempt
  • last-ditch attempt
  • last-ditch effort
  • last-gasp effort
  • last-ditch
  • last gasp
  • last-gasp
  • stick at
  • keep at
  • keep at (someone or something)