North Melbourne defender Aiden Bonar has aggravated an old wrist injury and will undergo surgery next week in a huge blow to his preparation for the 2022 AFL season.
The 22-year-old's rehabilitation is expected to keep him out of full training for up to three months.
The latest setback comes after an ankle injury derailed Bonar's 2021 campaign following a strong start to the year.
"Aiden came back to the club in great nick after the break, so it's disappointing for him," Kangaroos football manager Daniel McPherson said.
"He suffered a slight injury to the wrist in round five this year but it wasn't enough to sideline him at the time.
"He was fine heading into pre-season and had been training without any issues until an innocuous incident in a drill last week caused the old injury to resurface.
"He'll have the surgery next Monday, and will be back into his running program shortly after that."
North Melbourne finished last in 2021 with four wins and a draw in David Noble's first season as coach.
But they have been buoyed by the arrival of No.1 draft pick Jason Horne-Francis and are expected to build on an improved second half of the year.
