Exciting 200-centimetre prospect Tom De Koning injured his knee recently in a VFL hit-out and despite some promising senior performances last year from Patrick Kerr, Casboult is still seen as the first reserve for tall forwards.
Adding to his chances of being selected is the ruck problems the Blues continue to ponder.
Former Greater Western Sydney big man Andrew Phillips has impressed in the opening two rounds in the absence of Matthew Kreuzer, but the Blues believe he needs more support and they would prefer to keep young gun Harry McKay closer to goal.
Casboult has been employed as a part-time ruckman before and his selection against the Swans would go some way to solving both of those issues.
Carlton say Kreuzer would have played in the VFL this week if they had a game but instead will take part in internal game play with a view to being available next week.
The Blues may be buoyed, however, by the return of crucial key defender Caleb Marchbank, who has missed the start of the season with a back issue.
The former Giant would be a welcome return for Brendon Bolton, who has to work out how to stop Swans spearhead Lance Franklin.
Franklin has a strong recent record against the Blues, having kicked 13 goals in his past two outings, including a bag of 10 when playing on Liam Jones.
Both sides will be looking to avoid a 0-3 start to the season.
Carlton have beaten Sydney just once in their past 10 attempts, a match early in 2017 that left the Swans 0-6, before the Bloods went on a run of winning 17 of their next 19 games and playing in a semi-final.
If the Blues are beaten on Saturday, it would be their sixth 0-3 start in the past seven seasons.
Sam McClure won the Clinton Grybas rising star award at the AFL media association awards in 2015.