Finally out of the rehab room and sporting a new number, Sydney ruckman Sam Naismith has declared himself ready to go in 2020, after missing the last two AFL seasons.

The 27-year-old big man has played just 28 games, including the 2016 Grand Final, in seven seasons, three in which he didn't tally a senior match.

He missed the 2015 campaign due to glandular fever and osteitis pubis and all of 2018 and 2019 after undergoing a knee reconstruction.

Naismith played four NEAFL games last year, including a preliminary final but the Swans decided against giving him a match in the senior side.

"I remember towards the end of the year I was telling 'Horse' (Swans coach John Longmire) to put me in because I was pretty confident that I was ready to go and it was hard sitting on the sidelines losing week in and week out and wanting to contribute," Naismith told AAP.

"But I think he was pretty comfortable to say 'just wait.'

"I know they are excited to have me back and I'm excited to be in there so 2020 is where it's at.

"I've had a pretty horror run with injuries but that's all behind me now."

The 206cm ruckman ticked off another box on Friday when he had his final non-contact session.

"I'm definitely on track for that first Marsh series game on (February 29) and I'll be in for round one," added Naismith, whose last senior game was a 2017 semi-final.

Naismith is confident he can help Sydney turn around their fortunes after they missed the finals for the first time since 2009.

"We looked at our midfield and our stoppage setups and especially our centre bounce, where we were lacking throughout the year," Naismith said.

"I'm confident that I can help the team with that.

"If we can get back to what we were doing in 2016 and 2017, I'm super confident that we're going to go a long way."

Naismith wore number 35, but has switched to 10 this year after the previous owner, Zak Jones, moved to St Kilda.

"Coming into my eighth year I haven't had much luck and I was really low there for a bit of time and I wanted to mentally just freshen up and give myself a clean slate coming into this year," Naismith said.