The most common and most likely answer to this crossword clue is the 10 letter word ALL-TICKET
A
L
L
-
T
I
C
K
E
T
Buddy explains!
The straight part
We know that "Possible designation of big match" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case possible designation of big match = all-ticket.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ALL-TICKET mean?
ALL-TICKET adjective- Of a sports match or similar event: requiring the purchase of a ticket in advance.