Variable heating around back of club? It's secured (2,3,3)
I believe the answer is:
in the bag
'secured' is the definition.
(I've seen this before)
'variable heating around back of club?' is the wordplay.
'variable' indicates anagramming the letters.
'around' is an insertion indicator.
'back of' says to take the final letters.
The last letter of 'club' is 'b'.
'heating' anagrammed gives 'intheag'.
'intheag' going around 'b' is 'IN THE BAG'.
'it's' acts as a link.
(Other definitions for in the bag that I've seen before include "almost secured" , "Virtually secured (informal)" , "like cat incapable of ratting?" , "As good as done" , "purchases here?" .)