Crossword Genius

Have no energy during run — the result of blow? (5,3)

Ross

I believe the answer is:

black eye

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

'of blow?' is the definition.
The definition suggests a singular noun which matches the answer.

'have no energy during run the' is the wordplay.
I cannot quite understand how this works, but
'energy' could be 'ke' (K.E. is an example) and 'ke' is present in the answer.
This may be the basis of clue (or it may be nonsense).

'result' acts as a link.

Can you help me to learn more?

(Other definitions for black eye that I've seen before include "result of being punched?" , "Shiner" , "Result of blow to optic" , "Visible sign of a fight" , "Bruised facial area" .)

I've seen this clue in The Times.
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