Hull are set to part company with two of their close-season signings, former Wigan prop Eamon O'Carroll and ex-Leigh scrum-half Jamie Ellis.
Both players have struggled get much game time in their first season at the KC Stadium and have been given permission to speak to other clubs.
O'Carroll, 25, who joined the Black and Whites on a three-year deal, is thought to be on his way to Widnes while Ellis is poised to rejoin his old Leigh boss Ian Millward at Castleford.
Hull director of rugby Shaun McRae said: "We've got nothing but the greatest respect for Eamon.
"He is a fantastic player to have at the club. His commitment on and off the field cannot be faulted and he is a popular character, certainly amongst our players and fan base.
"However, as is sometimes the case in sport, the current circumstances haven't quite suited the player or the club.
"Eamon is now free to speak to other clubs and we understand there has been significant interest."