Danny Buderus’ chances of making an immediate impact as interim Newcastle coach have already been dealt a blow with the loss of star five-eighth Jarrod Mullen to a season-ending injury.

The Knights announced their talented playmaker will have surgery on his troublesome toe this Thursday, meaning Mullen could be sidelined for a reported four months.

The 28-year-old suffered the injury in May and took 10 weeks off before making his return against Canberra earlier this month, and has been a day-to-day proposition since.

He played a starring role in Newcastle’s 30-2 win over Gold Coast 10 days ago and his loss is huge for the struggling Knights who sit just two points off the last-placed Wests Tigers.

Veteran Kurt Gidley is expected to see out his final year at the Knights in the No.6 jersey in place of Mullen, as Newcastle face a huge battle to avoid the wooden spoon.

The blow comes a day after Newcastle sacked coach Rick Stone, replacing him with club legend Buderus in a caretaker role as Newcastle begin the search for a new mentor for the 2016 season.

Chief executive Matt Gidley also warned the under-performing playing group the bloodletting would not stop at Stone, promising players they had the final six rounds to prove they really wanted to be at the club.