Drops behind cascade covering footballer (5,4)

I believe the answer is:

falls back

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'drops behind' is the definition.
The answer and definition can be both to do with motion as well as being verbs in their -s form.
Maybe they are linked in a way I don't understand?

'cascade covering footballer' is the wordplay.
'cascade' becomes 'falls' (synonyms).
'covering' is a charade indicator (letters next to each other) (on top of in down clue).
'footballer' becomes 'back' (back is a kind of footballer).
'falls'+'back'='FALLS BACK'

Can you help me to learn more?

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

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