PROMISING Gold Coast ruckman Zac Smith is still some way off making an AFL return after being placed on the club's long-term injury list.

Smith tore his anterior cruciate ligament in round eight last year and had a knee reconstruction, forcing him to miss the start of this season.

In his place, rookie Andrew Boston has been elevated to the Suns senior list, an AFL spokesperson said on Wednesday.

Earlier, Gold Coast midfield coach Matthew Primus said he was confident the 205cm big man would return to his athletic best.

"He is still only young. He will take a while coming back as does everyone coming back from a knee (injury), but he's got all the attributes to be a No.1 ruckman and a ruckman at this club for another decade or so," Primus said on goldcoastfc.com.au.

The Suns are in a strong position to cover Smith in the early stages of the season, with young pair Tom Nicholls and Daniel Gorringe impressing through the pre-season.

Primus said it would take Smith some time to regain his form once he returns to match practice.

"He feels really good now, it's about holding that little bit back until that knee's as good as it can get," Primus said.

"He'll take a month or so to get his touch back, but it is good it has happened early in his career, if there is a good time for it to happen."

24-year-old Smith has played 44 games for the Suns since making his debut in 2011.