The Penrith Panthers are set to be without new recruit Tevita Pangai Junior for Saturday's critical clash with the Sydney Roosters.

Reports have emerged from Channel 7s Michelle Bishop that Pangai Junior will pull out of the game due to a personal issue, while The Daily Telegraph's Christian Nicolussi reported that he and his partner were dealing with a "deeply personal and sensitive matter."

Pangai Junior had been named on the bench for the match, which was due to be his first hitout in a Penrith jumper.

Penrith signed Pangai Junior on a short-term contract for the remainder of the year after committing to join the Canterbury Bulldogs from the beginning of 2022 as a marquee recruit to the rebuilding club.

The 25-year-old said told the media on Thursday that he was thrilled with the chance Penrith have provided him.

"The first day has been good. I've seen a lot of rep players here, and you know, just picking their brains. Especially Isaah Yeo who has been really good for me," Pangai Junior said.

"I just want to earn the boys' respect and do the little things right," he said when asked what he wanted to achieve during his stint at Penrith.

With the prize recruit now set to miss the match, Penrith will likely turn to J'maine Hopgood or Izack Tago to join their interchange bench ahead of the game.

Teams will be reduced from 21 to 19 players for the game at 5:30pm today.

Penrith are yet to make comment, however, it's understood he had the club's full support.