The Manly Sea Eagles have revealed forward Nathan Brown has suffered a ruptured biceps and will miss an extended period.

The forward suffered the injury during Round 17 against the Wests Tigers, and has now had surgery during the club's bye week to repair the injury.

It means he will be unavailable for a period of between nine and twelve weeks, starting with this weekend's clash against the South Sydney Rabbitohs.

The painful injury leaves Brown with a chance of returning before the end of the regular season, although he will need his recovery to go as well as it can for that to be the case.

At any rate, he will be out until at least Round 26 when Manly travel to Kogarah to clash with the St George Illawarra Dragons.

Only a single bye remains for the Sea Eagles - to be had next weekend after Game 3 of the 2025 State of Origin series - so they will be without one of their key enforcers for a number of games.

Coach Anthony Seibold has not gone for a forward to replace Brown, but rather recalled winger Tommy Talau on the bench, with hooker Jake Simpkin, and forwards Ethan Bullemor and Toafofoa Sipley the other players on the pine for the game.

Should Brown's recovery blow out towards 12 weeks, he will need Manly to qualify for the finals to be able to play again this season.