Hull forward Danny Tickle is facing at least two months on the sidelines with a knee injury.
The 30-year-old England international was injured during the second half of Sunday's victory over Catalan Dragons and was placed in a temporary brace after the game.
He has now undergone further tests which have ruled him out for a lengthy period, although Hull coach Peter Gentle will soon have options to replace him in the back row.
Club captain Gareth Ellis is closing in on a return to action and is back in training after his protective boot was removed following his foot injury.
The 31-year-old is now awaiting the results of a scan which will determine his comeback date.
Liam Kent is also back in the fold after undergoing shoulder surgery in the autumn and is set to feature for the York City Knights in Sunday's Championship game against Dewsbury.