The Wests Tigers signed New Zealand and St George Illawarra Dragons forward Russell Packer on a four-year deal.
Packer, 27, is a veteran of 142 NRL games, having played for the New Zealand Warriors before his move to the Dragons.
He is also a three-time international and joins the Tigers until at least the end of 2021.
"Russell has been one of the standout front-rowers in the NRL this season," Tigers head coach Ivan Cleary said.
"He's a no-nonsense front rower, he really knows what his job is and he delivers and I think he's only going to get better.
"I think he's going to have a very strong leadership role here. He's got a great story, a story of hard knocks and coming out the other side, and that will resonate with lots of the boys here.
"He's very keen to help us regrow what we have here at Wests Tigers, and they're the sort of guys we want on board."