South Sydney Rabbitohs young gun Blake Taaffe is in considerable doubt to take his spot for the club against the New Zealand Warriors during Magic Round as he battles a case of flu.

While unclear at this stage just how much chance he is of getting off the sick bed to play during the NRL's biggest round of the season, Latrell Mitchell's replacement didn't train on Monday.

Rabbitohs coach Jason Demetriou confirmed the news on Tuesday morning in an interview with the Sydney Morning Herald, suggesting at the time that Kodi Nikorima - who has only joined the club this week on an immediate swap from the New Zealand Warriors - could be Taaffe's replacement at the back for a clash against his old club.

“Kodi will definitely play this week, we’ve got some decisions in and around availability, but at this stage he’ll probably be our No. 14,” Demetriou told the publication.

“Blake is off crook today. The last few weeks we haven’t been able to get through a captain’s run without losing players.

“Kodi can play that utility role. He loves playing No.7, but he can also play fullback. What I will say is he won’t be playing No.9 while he’s here. I see his value as an attacking weapon, but more in the six, seven and one role."

According to The Daily Telegraph's David Riccio though, who appeared on Fox Sports' NRL 360 on Tuesday evening, Taaffe will need to show "considerable" improvement to play.

“Taaffe is struggling with the flu, and he will need to show significant improvement at tomorrow's training session to be cleared to play this weekend against the Warriors,” Riccio said.

Nikorima has traditionally played at either half or hooker in his utility role with the Warriors, making it something of a surprise that he would be considered to play at the back.

However, the Rabbitohs' squad has few options to shift to the back if Taaffe is out given Latrell Mitchell's long-term layoff with a hamstring injury.

The only other realistic option in the named 24 would include moving Alex Johnston to the back and bringing Josh Mansour in on the wing.

The Rabbitohs play the Warriors on Saturday afternoon, with kick-off set for 3pm (AEST). Teams will be trimmed to 19 players on Friday afternoon, 24 hours before kick-off.