Cattermole admits his former team-mate has been a miss.
"Jack's a good friend and good player. We've missed him," he told the Mail on Sunday. "That's been a bit of a loss for us. He made a decision to move on and good luck to him.
"I think if he'd gone to any other club he would have got a good reception because he did well for Sunderland.
"Obviously, where he's chosen to go to, it's going to be difficult for the fans to take."