While he's set to sit out a week regardless, the Sydney Roosters are sweating over Joseph Manu's cheekbone after the centre's face 'blew up' during their clash against the South Sydney Rabbitohs.

The grudge match to end all grudge matches, Manu was pivotal during the 20-18 victory over the Roosters' nemesis, however it wasn't all cheers and celebrations post-match for the club as fears for the 26-year-old's face arose.

Manu has a complicated past with facial fractures, his face ballooning in 2021 after Latrell Mitchell ended his season with a monster hit, before fracturing the other side of his face during a training trip in Queenstown last month.

The Kiwi international made a stellar chase-down effort on Isaiah Tass in the dying minutes of the contest, knocking the ball free as the Rabbitohs' centre drew closer to the line, only to mistime his tackle and clip Tass in the face.

While the South Sydney centre was fine, the same can't be said for Manu, who not only was charged by the match review committee following the hit, but started a post-tackle melee which may have re-injured his cheek.

Manu was sin-binned, and walked up the tunnel with an inflated cheek and blood pouring from his face, leaving Chooks officials with fears that the New Zealander had injured the same cheekbone he returned from last week.

The 26-year-old was slapped with a grade two careless high tackle charge for the incident, and faces one week on the sidelines with an early guilty plea, or risk doubling it if he fails in contesting it at the judiciary.

Roosters' coach Trent Robinson was hopeful his star outside back wasn't set for another stint on the sidelines.

“He‘s cut open so I'd say he needs some stitches,” Robinson said post-match.

“I am hoping not [a re-fracture], it blew up, but I'm hoping not.”

The Roosters will have the bye in Round 4 before facing Parramatta the following week, which Manu will miss regardless through suspension, handing the centre a three-week spell to prove his fitness before marking Melbourne's Justin Olam in Round 6.