A positional switch is set to revitalise Charlie Constable's career at AFL level, with Gold Coast seriously considering the former Geelong midfielder as a starting half-back for round one.

Constable, who played 12 games in four seasons at the Cats before moving to the SUNS a little over a year ago, has shone during pre-season in a defensive role.

The 23-year-old was Gold Coast's medi-sub twice last season, getting on the field briefly in round 23, and spent the final weeks of the VFL season at half-back.

Defensive coach Tate Kaesler told AFL.com.au there was a lot to like about Constable in his new role.

"What we do know is he's a great ball-user," Kaesler said.

"In the off-season we had a chat around where he thinks he can fit and what other potential he has and half-back came up.

"He went away and got himself as fit as he's ever been.

"His composure with ball and the way he can slice opposition teams apart is something I value, but what he's been working on big time is his defensive craft.

"We've exposed him to being that third tall as well, so he can play in different layers in that defensive part of the game.

"It's not a second role for him, we're looking at it as a permanent position."

Constable, who stands at 193cm, was caught in a midfield logjam at the SUNS, behind Touk Miller, Matt Rowell, Noah Anderson, David Swallow and youngsters Sam Flanders and Alex Davies.

The door is ajar to start the season at AFL level with Wil Powell (hamstring) and Lachie Weller (recovery from knee reconstruction) racing the clock to be available.

Kaesler said Constable had quickly won over his backline mates.

"The most important thing he's earned is the trust from his teammates," he said.

"There's nothing better than your teammates telling you they love playing with you.

"He's a guy really pushing. It'll be really good to see how he'll go in the trial games and see if he can cement his spot.

"He's very diligent, wants to get better and be the best version of himself he can be."