BRISBANE is trialling the shock move of playing Cam Rayner in defence.

The former No.1 draft pick has been used in the back half during match simulation sessions this pre-season, with coach Chris Fagan confirming to AFL.com.au the move was a serious consideration.

Rayner has played as a third tall defender, one with some freedom to intercept mark, and on Wednesday was locked in on manning Lincoln McCarthy.

Fagan said there were a number of reasons for the experiment.

"He's a great team man and at under-16s he was an All-Australian as a half-back flanker, so he's actually got experience playing down there," he said.

"If you play down back, you learn a lot of things about being a forward. You learn as a backman what really challenges you, so it's a good lesson in reverse for Cam.

"He looks quite a natural down back at the moment.

"He's played all the practice matches there and we'll just weigh it up when we get to the season which way we go with him."

Rayner has played 87 games in his five seasons with the Lions, kicking 81 goals in a predominantly forward role.

After coming back last year from a reconstructed knee that wiped out his 2021, Rayner missed just one game through suspension and spent more time in the midfield than ever before.

However, with the additions of Josh Dunkley and Will Ashcroft over the off-season, the battle for midfield minutes has become a whole lot hotter, and Fagan believes in adding another position to the powerful Victorian's repertoire.

"He's also one of those blokes that's a real competitor and a real teamwork man," Fagan said.

"He's got that sort of brotherhood, mateship thing about him that suggests that he might be decent down back, and he's a really good intercept marker.

"You've got to experiment. You don't get better if you don't try new things."

Rayner's move is just one piece of a backline puzzle that still needs to be solved following the placement of Marcus Adams on the inactive list with complications to a concussion he suffered late last season.

While Fagan said the key defensive vacancy offered opportunities for others, including Jack Payne, his primary concern lay with Adams.

"He's just getting better very slowly. It's a little bit of improvement and then a little bit of going backwards," he said.

"I don't know how long it will take.

"I just hope he does come right, and that's not to play football again necessarily, that's to function and live normally and do all those day-to-day things we take for granted

"That's the priority. It'd be nice if he got back to play, but that's not the be all and end all."