Sydney ruckman Sam Naismith is expected to return from a knee reconstruction within the opening six weeks of the home and away season, coach John Longmire says.

Naismith has not played a senior game since the Swans' loss to Geelong in a 2017 semi-final, having ruptured his right anterior cruciate ligament at training last March.

Longmire told radio station SEN on Thursday morning Naismith, 26, had made good progress since undergoing another operation on his knee in December.

"He's going OK, he's running, he's not training yet, so he won't be available for the start of the season," Longmire said.

"He had the knee reconstruction last year and he had a minor cleanout just before Christmas and so that's helped him get through so far.

"We're not pushing him along too hard. He's a significant player for us in the ruck and missed all of last year, so we hope to get him back within that first four to six weeks."

Longmire said versatile tall Sam Reid was set to return from an injury-plagued 2018 season.

Reid has not played a senior game since round three last season following a quad injury and Achilles tendon surgery last July.

"Reid has been training really well, which has been fantastic," the Swans coach said.