MELBOURNE has suffered an early pre-season blow, with key defender Gabby Colvin rupturing her left ACL.

The 31-year-old injured her knee at training, changing direction while attempting a tackle, and has been ruled out for the season.

It opens the door for a round one club debut for recruit Charlotte Wilson, who crossed from Carlton during the AFL Sign and Trade period, while tall Tahlia Gillard also played three games in defence in her debut season.

Gabby Colvin during a Melbourne AFLW training session at Gosch's Paddock on November 9, 2021. Picture: Getty Images

Colvin produced arguably a career-best game during the 2022 AFLW Grand Final loss, recording 12 disposals and eight intercepts.

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She will be placed on the inactive list, and her spot in the squad of 30 will be able to be replaced by an additional selection in next Wednesday's NAB AFLW Draft.

The Dees already have former St Kilda co-captain Rhi Watt (ACL) on their inactive list.