Thoughtful judge supporting argument against team (11)
I believe the answer is:
considerate
'thoughtful' is the definition.
(associated in meaning)
'judge supporting argument against team' is the wordplay.
'judge' becomes 'rate' (rating is a kind of judging).
'supporting' is a charade indicator (letters next to each other) (in a down clue, some letters go below others).
'argument against' becomes 'con' (as in pros and cons).
'team' becomes 'side' (both can mean a sports team).
'con'+'side'='conside'
'rate' after 'conside' is 'CONSIDERATE'.
(Other definitions for considerate that I've seen before include "Mindful of others' well-being" , "Showing care" , "Careful not to harm or inconvenience others" , "Kind" , "Thoughtful for the feelings of others" .)