Global circumnavigator who'd have been anonymous had he lost heart (5)

I believe the answer is:

anson

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'global circumnavigator who'd have been anonymous' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'had he lost heart' is the wordplay.
'had he' becomes 'ans' (I can't explain this - if you can you should give a lot more credence to this answer).
'lost' becomes 'gone' (similar in meaning).
'heart' says to take the centre.
The centre of 'gone' is 'on'.
'ans'+'on'='ANSON'

Can you help me to learn more?

(Another definition for anson that I've seen is " George ____, circumnavigator and admiral, 1697-1762".)

I've seen this clue in the Evening Standard.

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