SYDNEY, AUSTRALIA - JUNE 15: Joseph Manu of the Roosters evades the tackle of Morgan Harper of the Bulldogs during the round five NRL match between the Canterbury Bulldogs and the Sydney Roosters at Bankwest Stadium on June 15, 2020 in Sydney, Australia. (Photo by Mark Metcalfe/Getty Images)

Sydney Roosters coach Trent Robinson has confirmed Joseph Manu's hamstring injury is "mild", but the club will still be sweating on the result of scans this week.

The star centre, who played fullback in the 32 points to 8 win over the Wests Tigers as the tri-colours kept their finals chances alive, lasted just 24 minutes before hobbling from the field with a suspected hamstring injury.

Last year's Golden Boot winner had been filling in at the back for James Tedesco, who missed the game against the Tigers with a concussion, and, given his history of head knocks, is no guarantee of playing against the South Sydney Rabbitohs next weekend.

It could leave the Roosters looking at a third-string fullback option.

"It's mild, but he still had the leave the field so it's never a good sign," Robinson said during his post-match press conference.

The NRL Physio said it looked a "pretty typical hamstring strain" and that he would be unlikely to play next weekend against the Rabbitohs.

The Roosters have just six days on their turnaround before taking on the Rabbitohs in the crunch game.

Meanwhile, Robinson confirmed both Victor Radley and Billy Smith were fine after copping various forms of head knocks during the game.

"It's just eight stitches and a bit of a shiner [for Radley]," Robinson added.

"Billy [Smith] got a poke in the eye and he will have a bit of a shiner as well."

Robinson was also quizzed on Brandon Smith who had appeared to come from the field with a shoulder injury, but the coach said it was a stringer and he was also fine.

"No, that was okay, it was a stinger. I took him off when Sam [Walker] came back on the field, so Sandon went in and then I think Billy went down a minute and a half after that, so he [Smith] went straight back out there," Robinson said on the off-season recruit.

The Roosters have a long casualty list heading into the finals, with the likes of Sitili Tupouniua and Connor Watson still featuring and unlikely to return this year.