Carefully examine a broken fist (4)
I believe the answer is:
'carefully examine' is the definition.
'sift' can be an answer for 'examine' (thesaurus). I am unsure of the 'carefully' bit.
'a broken fist' is the wordplay.
'a broken' is an anagram indicator.
'fist' is an anagram of 'SIFT'.
Can you help me to learn more?
(Other definitions for sift that I've seen before include "Separate out - examine closely" , "Filter, riddle" , "Use fist to pass through perforated container" , "Sieve, examine closely" , "Analyse carefully in fist" .)