Is this kind of keeper inexperienced?
I believe the answer is:
green
'inexperienced?' is the definition.
(similar in meaning)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for green that I've seen before include "Naive; colour" , "The colour of inexperience" , "right environmentally" , "Grassy enclosure, in a village say" , "one of eighteen" .)