Boris playing intellectual game, heavens above, admitting 'I haven't a clue' (7)
I believe the answer is:
spassky
'boris playing intellectual game' is the definition.
(Boris Spassky is a chess grandmaster)
'heavens above admitting i haven't a clue' is the wordplay.
'heavens above' becomes 'sky'.
'admitting' is an insertion indicator (admit can mean to welcome in or accept).
'i haven't a clue' becomes 'pass' (you might say 'pass' to skip a question).
'sky' going around 'pass' is 'SPASSKY'.
(Other definitions for spassky that I've seen before include "one renowned on board" , "He has often checked" , "prime mover?" , "Russian world chess master in early 1970s" .)