Newcastle captain Kalyn Ponga has made himself unavailable for Australia's World Cup team to focus on the Knights' pre-season training.
Ponga informed Kangaroos coach Mal Meninga on Wednesday of his decision to rule himself out possible selection for the tournament, which starts next month in England.
The Knights and Queensland fullback missed the last month of the NRL season due to repeated concussions, with his club finishing in 14th spot.
The 24-year-old was also recently cleared of any wrongdoing after being filmed coming out of a toilet cubicle in Newcastle with Knights teammate Kurt Mann.
"I understand the potential opportunities that may be missed by this decision, however, due to the year we have endured, I really want to commit on the upcoming pre-season," Ponga said in a club statement.
"My focus will sit firmly with nailing pre-season from the start, and I believe this decision is in the best interest of myself and the Knights."
