The centre, who has turned into one of their most consistent, through his 12 appearances this season, has had to withdraw from the clash due to an ear infection.
In a statement, Cronulla said the 24-year-old was ruled out by the club doctor earlier today, with youngster Jonaiah Lualua added to their 19-man squad.
Utility Luke Metcalf would be the player added to the interchange bench, with Billy Magoulias currently listed alongside Metcalf as the other reserve option in their 19-man squad, which was cut from 21 on Saturday afternoon ahead of the supposed Sunday kick-off.
Ramien has averaged 131 metres per game this season, while also making 76 tackle busts in his 12 games, causing constant headaches for opposition defensive lines.
The game was pushed back a day following Saturday's snap lockdown in Queensland, which forced all of those games to be postponed. The three Saturday fixtures were played yesterday at Suncorp Stadium with no crowds.
Manly and Cronulla will be the final game of the round at 8:05pm this evening, following the Gold Coast Titans and Canterbury Bulldogs, to be played at 6pm. Both games will also be held at Suncorp Stadium.