Sleeping topless can be awkward (9)
I believe the answer is:
lumbering
'awkward' is the definition.
(I've seen this before)
'sleeping topless' is the wordplay.
'sleeping' becomes 'slumbering' (synonyms).
'topless' means to remove the first letter.
'slumbering' with its initial letter taken off is 'LUMBERING'.
'can be' is the link.
(Other definitions for lumbering that I've seen before include "Awkward" , "Ponderous" , "Moving in heavy clumsy way" .)