Battling longer than the others, show endurance? (4,3)

I believe the answer is:

last out

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I'm afraid I can't even guess how this answer relates to the clue.

(Other definitions for last out that I've seen before include "Survive for as long as is required" , "one leaving after everyone else" , "Keep on going" , "Endure" , "Manage to survive" .)

I've seen this clue in the Evening Standard.

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