Border found batsman's top edge (4)
I believe the answer is:
brim
'border' is the definition.
(I've seen this in another clue)
'batsman's top edge' is the wordplay.
'top' says to take the initial letters (in a down clue, the first letter is top).
'edge' becomes 'rim' (rim is a kind of edge).
The first letter of 'batsmans' is 'b'.
'b'+'rim'='BRIM'
'found' is the link.
(Other definitions for brim that I've seen before include "Lip; part of a hat" , "Peak (of cap); be very full" , "Lip; part of 6 Down" , "Cup's lip" , "'Edge, like that of a hat (4)'" .)