Crossword Genius

Seeking red left over (5,5)

Ross

I believe the answer is:

going spare

I'm a little stuck... Click here to teach me more about this clue!

'seeking red' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'left over' is the wordplay.
'left' becomes 'going' (I can't explain this - if you can you should give a lot more credence to this answer).
'over' becomes 'spare' (I've seen this before).
'going'+'spare'='GOING SPARE'

Can you help me to learn more?

(Other definitions for going spare that I've seen before include "having been made redundant?" , "Getting angry" .)

I've seen this clue in the Sydney Morning Herald.
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