Back rower Jack Digby arrives in Doncaster from current Championship Cup holders Ealing Trailfinders, whom he originally joined in 2021.
Jack, who was originally born in London but grew up in Australia, scored 5 tries in his 2 seasons with the Trailfinders in the capital.
Before making the switch to England and the Championship, the 26-year-old played for Sydney Rays in the National Rugby Championship as well as Eastern Suburbs in the Shute Shield competition out in Oz.
With an ability to play at blindside flanker or number 8, Jack will provide some sought-after selection competition in the Knights back row.
The Aussie back rower is looking forward to immersing himself in a rugby environment which will best suit his abilities and seeing what the squad can produce as a unit.