Doncaster RLFC, who travel to League One leaders Bradford Bulls on Sunday, have been hit by a double injury blow.
Prop Brandan Wilkinson requires knee surgery on his anterior cruciate ligament and will be out for nine months.
Hooker Kieran Cross is also facing three months out after damaging his posterior cruciate ligament.
Dons chief executive Carl Hall said: “The club will be with both Brandan and Kieran all the way through their rehab process, this is devastating news for both players and our club.
“I am sure both players will come back bigger, stronger and faster from this as they are both very professional lads and will do everything right to get back on the field.”
Head coach Richard Horne added: “It’s tough to take losing both Brandan and Kieran, they’re great players and we will miss them while they are out.
“Myself and the club will continue to support the players throughout this time, and I wish them a speedy recovery, we now have to rally around as a squad and keep pushing on.”
Dons have slipped to seventh in the League One standings after losing three of their last four games.