ADELAIDE has been struck a blow on the eve of the AFLW season with scans confirming ruck Rhiannon Metcalfe requires a knee reconstruction.

The 27-year-old tore the anterior cruciate ligament in her left knee in an innocuous tackling incident during the Crows' trial game against Fremantle in Darwin on Saturday night.

Metcalfe will go under the knife within the next week and maintain a coaching role during the third season of AFLW.

FULL FIXTURE Check out when and where your club plays

"It's obviously very disappointing for us, as Rhi has been our No.1 ruck since we started," Crows general manager of football administration Phil Harper said.

"But she has a very tough character and the club will support her every step of the way through her rehabilitation."

Metcalfe's injury, and the departure of fellow ruck Jess Allan for work in the Army, will place further emphasis on first-year recruit Jess Foley.

Foley, 35, switched from basketball last year and is set to work in tandem in the ruck with Jasmyn Hewett and Sarah Allan.

INS AND OUTS Your club's full list for 2019

In positive news for the Crows, x-rays revealed Hewett had escaped a fracture in her right ankle after she failed to finish the trial game against the Dockers.

She is set to undergo more scans in coming days to assess ligament damage.

The Crows start their AFLW campaign against the Western Bulldogs at Norwood Oval on Saturday, February 2.