Reigning club best and fairest Kennedy will become the Swans first solo skipper since Stuart Maxfield in 2005 after Jack and McVeigh opted to step down earlier this week from the role they'd shared jointly over the past four seasons.

It coincides with Kennedy inking a long-term contract extension which keeps him at the club until at least 2020, ruling out any chance of him becoming the biggest fish in next year's free-agency market.

Longmire held talks with Jack and McVeigh about the club leadership structure upon returning to preseason training, having mulled over the idea of installing Kennedy in the weeks that followed Sydney's grand final defeat to the Western Bulldogs.

McVeigh suggested the possibility of returning to a single-captain structure, while Jack was strongly in favour of Kennedy taking over the role.

After discussions between Longmire, chief executive Andrew Ireland, head of football Tom Harley, and the match committee, the decision was made this week to appoint Kennedy.

It marks the end of six years in the job for McVeigh – he shared it in 2011 and 2012 with Adam Goodes. Jack meanwhile steps down after a tumultuous year off the field during which his falling out with parents Garry and Donna was made public.

Both players remain in an unchanged eight-man leadership group which was recently voted on by the players, as is customary at the Swans.

Luke Parker, Dan Hannebery​ and Dane Rampe​ will share the vice-captaincy role while Heath Grundy and Nick Smith round out the leadership arrangement.

"It just felt right for this particular moment," Longmire said of Kennedy's appointment.

"His consistency's remarkable, he just keeps lifting and getting better and better. We know he's an absolute professional the way he prepares and how he talks about things in meetings.

"All of those things come into the melting pot and add up to what we think will be a fantastic captain for us.

"There's no questions that having two ex-captains in your leadership group is an absolute positive.

"You really don't know what it's like until you've sat in the chair. We've got two players in that leadership group now that have sat in the chair and who have looked through the eyes that Josh is going to look through."

Kennedy's appointment and contract extension caps off another huge year for the 28-year-old who narrowly pipped Dan Hannebery to take out his third Bob Skilton Medal this year.

He was also the Swans' best player in the grand-final defeat to the Bulldogs.

"When the opportunity came earlier this week you certainly give it a lot of thought and it's just sinking in now, it's a little bit surreal," Kennedy said.

"We've got strong foundations at the club that have been set by the leaders before and excited with the list we've got at the moment too.

"The role I guess requires a lot more thought process for the team, how to make other people better, what John's thinking.

"Speaking with Kieren he said that Horse would call him on a Saturday Sunday and you almost get caught in his wake.

"I'm looking forward to the new challenge and trying to help this team."