The 21-year-old's body lay at the base of the headland separating Queenscliff and Freshwater beaches until just before 7pm Sunday evening, when members of the public alerted police.
News of his death came as a devastating blow for the Sea Eagles, with club officials describing him as a quiet, likeable and trouble-free youngster.
The Central Coast junior joined Manly aged 16 and spent his first four seasons rising through the S.G. Ball and Toyota Cup ranks.
Manly officials refused to comment publicly until the NSW Coroner makes an official finding, which is expected to be delivered today.
Instead, the club posted a short note on its Twitter account that read: "Tragic news for the club today. Out of respect for the family we'll make a statement at a more appropriate time."
But Sea Eagles officials are privately at a loss to explain the tragedy because Annear was in good spirits alongside fellow players at Friday night's function.