Created a sketch that's weird without single backtrack (4)
I believe the answer is:
drew
'created a sketch' is the definition.
(I've seen this in another clue)
'weird without single backtrack' is the wordplay.
'without' suggests deleting specific letters.
'single' becomes 'I' (one).
'backtrack' shows that the letters should be reversed in order (I've seen 'backtracking' mean this).
'weird' with 'i' taken away is 'werd'.
'werd' reversed gives 'DREW'.
'that's' acts as a link.
(Other definitions for drew that I've seen before include "was attractive" , "Made lines on a surface" , "Dragged, sketched" , "neither won nor lost" , "Made picture; pulled" .)