No striking evidence of injury? (4)

I believe the answer is:

scab

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

'evidence of injury?' is the definition.
(I've seen this in another clue)

I don't understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for scab that I've seen before include "Ignorer of strike" , "Crust forming over wound" , "One continuing to work" , "work when others are out" , "that blocks cut" .)

I've seen this clue in the Evening Standard.

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