ADELAIDE has re-signed youngster Andrew McPherson to a two-year contract extension, ensuring the defender will remain at West Lakes until at least the end of 2021.

McPherson, pick No.40 in last year's NAB AFL Draft, is set to play his first game in the SANFL this weekend after battling groin soreness for much of the season.

The 18-year-old South Australian said he was ecstatic to extend his stay at the club after originally being contracted until the end of 2019. 

"It's a great environment to be around at the club and everyone has been so welcoming in my first year," McPherson said. 

"To get drafted to Adelaide was awesome and to know that I will be here for at least a few more years is fantastic." 

Crows list manager Justin Reid believes McPherson will be one of the steals of last year's draft. 

"He's just returned to full fitness after an injury-interrupted start to the year and we look forward to him showing his ability in the second half of the season," Reid said.