Reach and grasp a tin opener (3,2)
I believe the answer is:
get at
'reach' is the definition.
(getting at is a kind of reaching)
'grasp a tin opener' is the wordplay.
'grasp' becomes 'get' (I've seen this in another clue).
'opener' suggests taking the first letters.
The initial letter of 'tin' is 't'.
'get'+'a'+'t'='GET AT'
'and' is the link.
(Other definitions for get at that I've seen before include "Pick on - gain access to" , "Nobble; gain access to" , "Reach - mean - attack verbally" , "Intend" , "Unfairly influence" .)