Grix has previously played for Halifax (in two spells), Doncaster, Limoux, Warrington, Leigh, Widnes and Wakefield Trinity, before joining Huddersfield in 2010. He has also captained Ireland, for whom he has won 11 caps.
“Scott is a vital part of what we do and he’s a player who has managed to find a real high level of consistency in his game over the last two years,” said Anderson.
“One of the reasons he has got to that level is that he is very, very consistent in training as well.
“He is a player that did it tough in the early part of his career, been here and there, but he’s found himself a home here and he is a good role model for our younger players at the club as he is the first on the training field and the last to leave.
“It is the example that he sets with the things he does pre and post training as he is very meticulous in his approach and turns up with a good attitude to play well.
“He is a very smart player, a very consistent player and a very good player for us.”