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Noticed energy peaked, with a thousand running out (6)

Ross

I believe the answer is:

espied

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'noticed' is the definition.
(I've seen this in another clue)

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(Other definitions for espied that I've seen before include "Watched" , "Caught sight of (archaic)" , "Saw (archaic)" , "Caught sight of (poetic)" , "Glimpsed" .)

I've seen this clue in The Independent.
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