Yallop said: “It’s wonderful news for us, and we are really happy to have David joining us.
“He has proved himself over the years, and it will be wonderful to have him – and to be able to manage and coach him will be a dream come true for me.
“I see him playing centrally in our league. We have to get him on the ball as much as we can, making us tick.
“It’s an athlete’s game here, played at a little less pace than the Premiership.
“I think it will suit his game wonderfully well, because he will get to play his football and he will enjoy the players we have here. He will fit in nicely with our group.”