Poor, as excuses (4)
I believe the answer is:
lame
'poor as excuses' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for lame that I've seen before include "game" , "Feeble; cripple" , "Disabled in leg or foot" , "Of excuse, weak and unconvincing" , "Halting or unconvincing like poor excuse" .)