Not to be approached -- like exhausted kangaroo?
I believe the answer is:
out of bounds
'not to be approached' is the definition.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for out of bounds that I've seen before include "taboo" , "Off limits" , "like an exhausted kangaroo?" , "Skipper so exhausted" , "lying beyond field of play?" .)