Good move for both.
Tierney played his part in GF and WCC wins. Decent on the wing but never good enough to be full back at Wigan. Surpassed by the young lads on the wing. Good move for him though.
Little disappointed we've let Gregson go, saw him potential playing loose forward in a few years time. Always done a good for us when needed, even playing 6 a lot in 2016. He'll be a superleague regular I'm sure in the coming years
Good luck to both, room for Kibula, Mullen, etc to step in.