Here top candidates, found lacking, go to one side (9)
I believe the answer is:
shortlist
'here top candidates' is the definition.
(top candidates appear on a shortlist)
'lacking go to one side' is the wordplay.
'lacking' becomes 'short' (to be short something is to lack it).
'go to one side' becomes 'list' (list can mean to tilt or lean).
'short'+'list'='SHORTLIST'
'found' is the link.
(Other definitions for shortlist that I've seen before include "suitable candidates" , "Final candidates" , "Ko-Ko had" , "Reduced size of field" .)