RISING Star winner Callum Mills has been training with the Sydney Swans' midfield in the pre-season as the club looks to extend the talented youngster's repertoire after his brilliant debut season at half-back in 2016. 

Sydney Swans' coach John Longmire told AFL.com.au it was a natural progression for the 19-year-old as he developed an all-round game.

Despite a hamstring injury affecting his finals, Mills was outstanding throughout the home and away season in the defensive role that has been a feature of successful Sydney teams for more than a decade.

His intercept marking and ability to win contests were features of the first-year player's season.

Longmire said the club planned to build the youngster's versatility as he matured and Mills would follow a similar development path to many Swans who had developed AFL careers before him.

"We've trained him a fair bit more in the midfield, knowing he can still go mid-half back," Longmire said.

"We think we have got some variety and options to go through that part of the ground."

The club's depth in the high defensive role is obvious with a number of players capable of filling the important role.

Longmire said experienced playmaker Jarrad McVeigh was certain to continue in a defensive role in 2017, while the hard working Jake Lloyd had also impressed as a running defender during the latter half of last year.

The coach said he was also hopeful rookie Colin O'Riordan and Nic Newman would have a chance in that role, and Zak Jones had shown he was more than capable of playing across half-back.

With the loss of Tom Mitchell to Hawthorn opening up a spot in the midfield, star forward Isaac Heeney is likely to spend more time up the ground than he had in his first two seasons.

His outstanding performances on the wing in the finals showed he was ready to take the next step in his development.

However, Longmire said Heeney would not be lost to the forward line as he could prove a dangerous proposition inside 50.

"He could still be a great forward for us too because he is so dangerous for us [with his marking] and he is such a beautiful kick," Longmire said.

"He's doing a lot of work in the midfield but we know we can still push him forward if required."

Sydney had seven players, including Mills, who made their debut in 2016 with only Melbourne and the Brisbane Lions extracting more games from players in their first season.

Yet the Swans still made the Grand Final.