Junior Sa'u, who played for Melbourne and Newcastle in the NRL, will switch codes at the age of 34 after joining an American Major League Rugby club.
Sa'u will move from Leigh in the UK Super League after becoming Washington Old Glory's first signing for the 2022 MLR season.
"It's exciting to have a player with Junior's resume at Old Glory," said head coach Andrew Douglas.
"He's a powerful, dynamic runner and a fearsome defender. His experience at his levels in League will bring confidence to other players.
"He's an exciting signing not just for Old Glory but for Major League Rugby as well."
Sa'u has spent the past eight seasons in Super League, six of them with Salford.
He also played for New Zealand in the 2009 and 2010 Four Nations Series before switching his allegiance to Samoa.
Sa'u made 86 appearances for Newcastle and four for Melbourne during his NRL career.
Australian Associated Press