The season ends early for Reds quartet
Physio Robert Magnusson said: "Dean will not be fit enough to play again this season, and we will see how he responds to treatment.
"Mark has a broken toe and a broken hand so he will not be ready to play again this season."
Left back Tony Gallimore joins the duo on the sidelines and has been sent to see a specialist in a bid to solve his knee problem.
Finally, midfielder Jacob Burns (ankle) could face up to two months in the treatment room.
Robert Magnusson said: “Jacob has an operation on Friday that will keep him out for six to eight weeks. He has an ankle injury but it is not a ligament problem”.