A judge applied but is rejected (7)
I believe the answer is:
refused
'is rejected' is the definition.
(I've seen this before)
'a judge applied' is the wordplay.
'a judge' becomes 'ref' (referee).
'applied' becomes 'used' ('use' can be a synonym of 'apply').
'ref'+'used'='REFUSED'
'but' acts as a link.
(Other definitions for refused that I've seen before include "turned down appeal" , "Declined, rejected" , "Not accepted" , "Said no (7)" , "Was unwilling to accept" .)