Despite initially believing he had done little more than aggravate his glute during Saturday's night's NAB Cup victory over Geelong at Patersons Stadium, scans since conducted by the Dockers have shown otherwise.
The scans have shown that Sandilands has sustained a partial tear to his hamstring tendon and while the injury will not require surgery, it is expected to take him up to eight weeks to recover from it.
That will mean that not only will the 30-year-old miss the rest of the pre-season for the Dockers, but likely at least the first four rounds of the home and away season proper against West Coast, the Western Bulldogs, Essendon and Hawthorn.
Sandilands was limited to just 14 games last year due to injury as well and now the Dockers will be placing a heavy reliance on Jonathon Griffin and Zac Clarke to step up in his absence and hold down the fort until he gets back.
Fremantle general manager football operations, Chris Bond said that Sandilands’ absence would provide opportunities for other players.
"It’s certainly unfortunate that Aaron will be out for an extended period of time, but we have great confidence in our structures and players to be able to fill the role," Bond said.