Can leave havoc on border (3)
I believe the answer is:
hem
'border' is the definition.
(thesaurus)
'can leave havoc' is the wordplay.
'can' becomes 'may' ('may' can be a synonym of 'can').
'leave' is a deletion indicator.
'havoc' becomes 'mayhem' ('mayhem' can be a synonym of 'havoc').
'mayhem' with 'may' taken away is 'HEM'.
'on' is the link.
(Other definitions for hem that I've seen before include "Bottom of a garment" , "Finished edge of a piece of cloth" , "Border; fringe" , "Double-backed border of a garment" , "Stitched edge of garment" .)