Carlton coach Brendon Bolton has defended out-of-sorts spearhead Levi Casboult, saying he is providing "a great target" in attack for the young Blues.

Casboult has assumed the mantle of Carlton's No.1 key forward this season following the departure of Lachie Henderson to Geelong at the end of last season, and Jarrad Waite's move to North Melbourne a year before that.

The 26-year-old has kicked three goals from the opening four rounds.

While the resetting Blues have struggled to provide Casboult with consistent and quality supply so far in 2016, the forward's goalkicking has regressed to the standard it was before he took significant steps working with former Pie and Kangaroo Sav Rocca last season, when he kicked 24.12.

Bolton was asked by reporters on Thursday whether Casboult was in danger of being dropped for this round's clash against Fremantle at Domain Stadium.

Although the Blues coach stopped short of guaranteeing the spearhead a spot in Sunday's 22, he praised the role Casboult had played for Carlton in 2016's opening four rounds in a way that strongly suggested he would play against Freo.

"Levi is an exceptional contested mark and he's giving us a great target up the ground and in deep," Bolton said. 

"In fact, he's as good as anyone in the competition in that area. He's working really hard on his goalkicking."

Scoring has been Carlton's biggest weakness this season as it opened the year with four losses to sit 18th on the ladder.

The Blues have kicked just 34 goals in the opening four rounds and are ranked 17th in the competition for scoring, ahead of only Essendon. 

Asked whether his team was further off the pace than he had expected, Bolton was emphatic that the Blues knew what was letting them down and were working hard to rectify it. 

"I think you feel off the pace if you're directionless and you don't know what areas you need to improve on, and our players are really clear individually and as a team on what we need to do to improve," Bolton said. 

"And a lot of it is about our polish and execution.

"Every game we want to score more than we do, but if you go into the space of worrying that's not going to be productive. 

"It's got to be about hard work and that's what we're doing day by day, step by step."

Bolton said the Blues would consider recalling tall forward Liam Jones for the Freo clash. The former Bulldog sits on top of the VFL goalkicking ladder with eight goals after two rounds, including five last weekend against Geelong.

Blues captain Marc Murphy wore a helmet at training on Wednesday as he recovered from a head laceration suffered in the loss to the Western Bulldogs last Saturday night.

Bolton confirmed Murphy would be fit to take on Freo, along with Dale Thomas (knee and ankle), while Andrejs Everitt should be available for selection after missing the past two rounds with a calf strain.