One of those doing the scoring determines whose name goes on the cup (8)
I believe the answer is:
engraver
'name goes on the cup' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps there's a link between them I don't understand?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for engraver that I've seen before include "Craftsman carving a design" , "one who writes cuttingly" , "One who cuts or incises" , "who makes an impression?" , "One who carves inscriptions into jewellery" .)