The forward suffered a fractured shoulder blade in a heavy tackle from Gold Coast Titan’s prop Ryan James in their Round 11 clash.
At first, it was expected the 22-year old would miss 12 weeks meaning he could feature in the Knights final few games, but now medical staff are advising otherwise.
Saifiti did not take part in Newcastle’s contact ball-work session on Monday, therefore suggesting a return in the near future might not be on the cards.
It adds to what has been a frustrating 2018 campaign for Saifiti as he has only managed eight appearances for the Knights this season after completing 39 games in the previous two seasons.
Partaking in five games for Fiji in last year’s World Cup, Saifiti will be looking forward to getting back on the paddock in the 2019 season.
Meanwhile, fan favourite Nathan Ross will miss a third consecutive week for Newcastle due to a groin issue but remains positive he can take the field for the Knights before the season is out.