Support set to remain (4,3)
I believe the answer is:
stay put
'remain' is the definition.
(thesaurus)
'support set' is the wordplay.
'support' becomes 'stay' (stay is a kind of support**).
'set' becomes 'put' ('put' can be a synonym of 'set').
'stay'+'put'='STAY PUT'
'to' is the link.
(Other definitions for stay put that I've seen before include "Remain in one place" , "Remain in place, don't move" , "Informally, don't move - remain in situ" , "Remain unmoving" , "Stick around" .)