Quiet! Let one on board with keel close to waterline (7-7)

I believe the answer is:

shallow-draught

'keel close to waterline' is the definition.
(a boat with keel its close to the water line)

'quiet let one on board' is the wordplay.
'quiet' becomes 'sh'.
'let' becomes 'allow' (synonyms).
'one on board' becomes 'draught' (piece in the board game draughts).
'sh'+'allow'+'draught'='SHALLOW-DRAUGHT'

'with' is the link.

I've seen this clue in The Guardian.

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