That won't be a problem (2,5)
I believe the answer is:
no sweat
'that won't be a problem' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for no sweat that I've seen before include "There shouldn't be any objection" , "Don't worry" , "fine" , "It's not a problem (result of using antiperspirant?)" , "OK" .)