Row about the right judge perhaps (5)
I believe the answer is:
trier
'judge perhaps' is the definition.
(I've seen this before)
'row about the right' is the wordplay.
'row' becomes 'tier' (a tier is a row of things).
'about' is an insertion indicator.
'the right' becomes 'r' (common abbreviation).
'tier' enclosing 'r' is 'TRIER'.
(Other definitions for trier that I've seen before include "Person attempting" , "One who perseveres" , "He's making an effort" , "One always ready to have a go" , "Test" .)