Level achieved by heartless golfer? (4)
I believe the answer is:
tier
'level' is the definition.
(synonyms)
'heartless golfer?' is the wordplay.
'heartless' says to hollow out the word (remove centre letters).
'golfer?' becomes 'tiger' (US golfer Tiger Woods).
'tiger' with its centre taken out is 'TIER'.
'achieved by' is the link.
(Other definitions for tier that I've seen before include "this person secures" , "One making knot - level" , "Hierarchical level" , "Row (of seats)" , "Rite about layer" .)