United previously eliminating clubs (3)
I believe the answer is:
one
'united' is the definition.
(as in a phrase like 'we are one')
'previously eliminating clubs' is the wordplay.
'previously' becomes 'once' (I've seen this before).
'eliminating' suggests deleting specific letters.
'clubs' becomes 'c' (abbreviation used in card games such as bridge).
'once' with 'c' removed is 'ONE'.
(Other definitions for one that I've seen before include "Individual" , "joke" , "both halves" , "Leading cardinal" , "Single, sole" .)