Crossword Genius

Leading group in distress (5)

Ross

I believe the answer is:

upset

'distress' is the definition.
(thesaurus)

'leading group' is the wordplay.
'leading' becomes 'up' ('up' can be similar in meaning to 'leading').
'group' becomes 'set' (set is a kind of group).
'up'+'set'='UPSET'

'in' acts as a link.

(Other definitions for upset that I've seen before include "turned over" , "Discountenanced" , "unexpectedly beaten?" , "'Disturbed, agitated (5)'" , "Out of sorts" .)

I've seen this clue in The Telegraph.
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