Head of football David Noble said coach Phil Walsh's nomination for who will captain the club next year would be put to the board just after Christmas.
If cleared, a skipper will be announced in early 2015.
Sloane and Dangerfield – who spent this year as acting captains in the absence of the injured Nathan van Berlo – are both front-runners for the full-time job.
Noble said the club would choose the best possible captain, regardless of their contract status.
"I don't see that as an issue at all; I think you put your best people in place that are going to lead your club," Noble said.
"That's what we're expecting them to do.
"Fairly soon after Christmas something will be presented to the board and that needs to be ratified and then we'll let everyone know."
After star forward Taylor Walker recently re-signed, the pair are the highest profile duo still to commit at West Lakes.
Midfielder Richard Douglas is another who falls out of contract next year.
Noble said it was vital for the club's future to keep the entire squad together.
"We know that's one of the important aspects of your list management and it's a trait of success," he said.
"There's no doubt, when you go back through clubs that are able to maintain a large group of players together collectively or a period of time – it definitely helps."
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