WALYALUP young gun Cooper Simpson can only recall playing one game at half-back as a junior footballer, but the fact it was a best-on-ground performance in a Grand Final is a positive sign for the positional switch he has made this season.

Drafted as a midfielder/forward, Simpson has been training at half-back since March after asking the Dockers' coaches if they saw an opportunity for him in the role at AFL level following backman Brandon Walker's shoulder injury.

Given the green light to join the defenders, Simpson has been a rebounding revelation in the seniors over the past fortnight after spending five weeks honing his new craft in the WAFL.

The 20-year-old isn't sure yet if it will be a long-term move, but he has enjoyed playing a new role and kick-starting the Dockers' ball-movement with his elite skills and decision-making.

"I haven't had much experience down there, but Mum and Dad like to bring up that I won a best-on-ground in the under 15s Grand Final playing half-back," Simpson told AFL.com.au this week.

"Then it's really only the short amount of time I've spent there this year, but I like it and it's a good change.

"There was a spot there when Brandon Walker went down, and I'd want to play any position just to play AFL.

"So I talked to the coaches a little bit about it and asked, 'What if I try myself off half back, do you reckon I can bring something to the table there?'"

Simpson was told that the coaches had thrown the idea around before and believed his skillset would suit the role, with Corey Wagner's move into the midfield also opening another opportunity for a creative playmaker.

As impressive as Simpson's ball-use and decision-making has been though, the key to making the move a success was going to be developing the mindset and lockdown skills of a defender.

Backline development coach Tendai Mzungu played a key role in helping Simpson learn his new craft at WAFL level, with an initial focus on the defensive elements of the role.

"I really bought into what defending is and connecting with teammates and had to learn that side of the position, so with Tendai we really dug deep and developed me in that area," Simpson said.

"My focus was to become a defender before any of that ball movement stuff, so getting my positioning right and my mindset to be a defender. That was new to me, so trying to wrap my head around that took a little bit of time.

"Then the ball movement and joining in offensively comes naturally to me, so we had a little bit of a focus on that, but our main focus was to defend first."

Simpson has taken to the role quickly and impressed with his ability to defend, position, and intercept, with fellow rebounder Jordan Clark playing a big role on-field with his direction and support.  

His ability to then switch modes and hit targets in the corridor was a standout feature against Greater Western Sydney, with Simpson growing in confidence with his ability to play an important role in the Dockers' ball movement.  

"It's a build-up of the weeks I've had down at Peel in that position, slowly gaining a bit more confidence each week in my ability to read the play and execute," he said.

"I guess my decision making and my foot skills are something that I work hard on, and something that comes to me naturally as well.

"So any chance I can get to take the game on when it's necessary or when I can, it's an asset that I can give to the team."