It's upsetting to get nil in the game, obviously (7)
I believe the answer is:
plainly
'obviously' is the definition.
(I've seen this before)
'it's upsetting to get nil in the game' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'nil' is 'inl' which is within the answer.
'game' could be 'p' (I have seen 'French game ' mean 'p' so perhaps 'game' could also mean 'p') and 'p' is located in the answer.
The remaining letters 'lay' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for plainly that I've seen before include "In unconcealed fashion" , "Simply" , "... without embellishment" , "Clearly" , "obviously" .)