North Melbourne suffered another blow to its injury-ravaged defence with Josh Goater rupturing an Achilles in the 39-point defeat to Greater Western Sydney.

Goater slumped to the ground after starting to run after Toby Greene when the Giants skipper made a lead inside 50, and immediately reached for his lower left leg.

The young half-back had to be helped from the field in the dying stages of the match at Engie Stadium and the Kangaroos confirmed on Saturday night that Goater has ruptured an Achilles.

"Josh is a young player, this is third year of footy, and if that's a ruptured Achilles I dare say his season is done, which is so sad,” Kangaroos coach Alastair Clarkson said.

"But that's the game that we're in. It's a really, really demanding game and, unfortunately, he's just going to have to rehab it well and get himself ready for next year."

GIANTS v KANGAROOS Full match coverage and stats

Goater was playing his 12th match as the Kangaroos look to rebuild their defence with Griffin Logue sidelined with a torn ACL, former skipper Jack Ziebell retired, and Ben McKay leaving as a free agent last year.

The 20-year-old had 10 disposals including four rebounds against the Giants, while his long-kicking out of defence was widely expected to become a weapon for the Roos this year.

Co-captain Luke McDonald is nearing a return from a hamstring injury as the Kangaroos look to bolster their under-siege defence that allowed the Giants to have 36 scoring shots from 60 inside 50s.

"It's just really disappointing for him for where he's at it with his career that he can't consolidate on his emergence into the side last year," Clarkson said.

"He played one game in his first year and played 10 last year, and this was going to be his step-up year. So that's disappointing for him. We're shattered for him."