CARLTON key-position player Lachie Henderson is expecting to play as a permanent backman in 2012 after developing in the role last season.

The 22-year-old former Brisbane Lion has appeared in both attack and defence in his 49-game career, but appeared regularly in the backline in the second half of last season.

He stood up against forwards including Jack Riewoldt, Michael Hurley, Drew Petrie, Lance Franklin and Nick Riewoldt, and became an important part of the Blues' line-up when key back Michael Jamison missed eight games with a knee injury.  

He has become stronger across the pre-season despite a slow start to training, and is ready to accept his days in the forward line are more than likely over.

"It took me awhile [to get used to defence]. I was getting asked about six weeks in if I was still a forward and I was telling the coaches I was," Henderson said on Friday, ahead of Carlton's round two NAB Cup clash against the Western Bulldogs.

"I'm enjoying it. I'm getting a lot more confidence from it, and the boys around me with Jeremy Laidler, Nick Duigan, Michael Jamison ... Chris Yarran and Aaron Joseph, we're getting a really good strong defensive group down there.

"Every time I kick a goal at training, I throw up they should put me back forward but ... I think it will be a permanent move."

Henderson has been in full training for two months and had a better pre-season than his last, which was ruined by a hip injury he needed repaired just before Christmas, 2010.

He said while the benefits of his summer program weren't obvious on the scales, he had noticed a difference when it came to his output in the gym.

"I don't really change weight too much very easily, I sort of stay the same, but I'm just trying to get a bit stronger and the weights are showing I've got a bit stronger so that's a plus," he said.

"I think that will show hopefully when round one comes around.

"I'm just enjoying playing some [practice] matches now leading into round one and I think it's going to help me a heap."

The Blues will take on the Bulldogs with a number of players missing, including captain Chris Judd, Jarrad Waite, Andrew Walker, Mitch Robinson,  Robbie Warnock, Duigan and Jamison, with the majority to return the following week.

Jamison (back) and Warnock (shoulders) are the only ones not expected to play, but Henderson says the Blues are hopeful the former will be right for the season opener against Richmond on March 29.

"[Jamison's] going very well. I think for those sorts of boys - Judd, Jamison - they were always going to play one to two NAB Cups, they don't really need a lot of match practice," he said.

"He's doing the same thing. It's a bit of a slow injury with the recovery; you can't really do a lot beside just let it heal, but he's on track."

Jennifer Witham is a reporter for AFL Media. Follow her on Twitter @AFL_JenWitham.