Hull forward Peter Cusack will be out for up to four months after dislocating his wrist in last weekend’s defeat against Warrington.
Cusack, 32, underwent surgery on his wrist today, which included a reconstruction.
Head Coach Richard Agar said: “It is a real blow for us, especially as Peter is such a consistent performer for us.”
Stand off Danny Washbrook, who was also injured against the Wolves, is to see club specialist Simon Roberts in Wrexham on Friday after an MRI scan revealed he had ligament damage to his knee.
Hull are waiting for the full prognosis of his injury before determining how long Washbrook is likely to be sidelined.
The Airlie Birds have won just two of their last eight Super League matches.