Members of pack close to tears after point of no return? (4)
I believe the answer is:
aces
'members of pack' is the definition.
(from a pack of cards)
'close to tears after point of no return?' is the wordplay.
'close to' suggests the final letters (the close/ending of).
'after' means one lot of letters go next to another.
'point of no return?' becomes 'ace' (tennis serve which is not returned**).
The final letter of 'tears' is 's'.
's' put after 'ace' is 'ACES'.
(Other definitions for aces that I've seen before include "They're high and low on cards" , "Champions" , "Case of top cards" , "Playing cards with single pips on their faces" , "Unreturnable services" .)