I'm lacking lustre in run-through (6)
I believe the answer is:
impale
'i'm lacking lustre in run-through' is the definition.
I can't tell whether this defines the answer.
'i'm lacking lustre in' is the wordplay.
'lacking lustre in' becomes 'pale' (I can't justify this - if you can you should believe this answer much more).
'im'+'pale'='IMPALE'
Can you help me to learn more?
(Other definitions for impale that I've seen before include "Pierce with lance etc" , "Kill by piercing with a sharp stake" , "Fix as on a sharp stick" , "transfix with sharp item" , "Kill by piercing with a spear or sharp pole" .)