Newcastle have 19 players already signed for 2028, among the most of any NRL club, but the crowded roster could make it harder to keep Mat Croker.
Rival teams are showing interest in the 27-year-old lock, who has no deal beyond 2027 and can receive formal approaches in just under two weeks, ahead of November 1.
The Knights are understood to be eager to retain him, though their salary cap is under pressure.
Croker's 2026 campaign was his best, helping Newcastle reach the grand final as he became Justin Holbrook's regular number 13.
He played all 28 possible matches, completed almost 93 per cent of his tackles and averaged 77 metres per game.
His support work away from the ball is less visible in statistics, while his appetite for leaving the Hunter remains uncertain.
His form is expected to earn him a pay rise after 2027, which Newcastle may struggle to fund.
The club is also balancing younger players and has reportedly made Bradman Best a low offer, with seven-figure contracts already in place for Kalyn Ponga and Dylan Brown.
Most clubs have fewer than 15 players contracted for 2028, while Croker has made 110 appearances since debuting for Newcastle in 2021 and has not missed a game in the past two seasons.