Nick Smith is determined to forge a comeback from injury next season, but the experienced Sydney Swans defender says he understands his long-term playing future is at risk.

Smith hasn't played since he ripped his hamstring tendon away from the bone against Melbourne at the MCG in Round 21 last year.

His body has rejected repeated attempts to get back to full training this season.

In eight seasons prior to this year, the premiership Swan and 2014 All Australian had averaged almost 23 matches a year.

The veteran managed to rehabilitate his dodgy hammy multiple times to the point where he could run in straight lines at moderate intensity, but every time he tried to push himself further, he was forced to back off.

Sydney's medical staff consulted specialists last month and it was decided more surgery was needed, which ended Smith's 2019 campaign.

Out of contract at the end of the year and still 4-5 months away from knowing if the operation was a success, the 31-year-old said he was confident he could play on in 2020, but that decision would be out of his hands.

The Swans lost Heath Grundy to retirement earlier this season and, with doubts lingering over the futures of Jarrad McVeigh and Kieren Jack, Smith knows there is a changing of the guard at Sydney. Even if he can get back on the field, there might not be a spot for him." 

"If the club still wants me and I can still go around again, good. If not, then that's life," he said. 

"If I was the club, I mean I'm 31 and I haven't played for a year, I wouldn't call it a risk, but do they give a young guy an opportunity instead?

"It probably depends on how the side is going. There are a lot of balls in the air at the moment so we'll just figure it out at the end of the year. 

"There's still plenty of unknowns but I'm pretty easy with that at the moment.

"If you're mentally ready and your body holds up, then why should age be a reason as to why you shouldn't play?

"I saw (Western Bulldogs defender) Dale Morris is 36 and he said the same thing (this week)."