That navigated by Crusoe? (6)

I believe the answer is:

course

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'that' is the definition.
Both the answer and definition are adverbs.
Perhaps you can see an association between them that I can't see?

'navigated by crusoe?' is the wordplay.
'crusoe' can be anagrammed to 'COURSE'.
But, I'm not sure how the anagram is indicated.

Can you help me to learn more?

(Other definitions for course that I've seen before include "fish, possibly" , "Pursue - career - run - series of lectures" , "Route; lectures" , "Route along which something travels" , "Mode, of action say" .)

I've seen this clue in the Evening Standard.

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