PORT Adelaide is uncertain when Orazio Fantasia will return from his latest injury setback.

Fantasia strained a thigh muscle on Saturday when playing his first game at any level this year, in Port's state league side.

The injury follows separate surgery on both knees in the past year which have curtailed his output. Fantasia's latest knee operation was in January this year.

The 26-year-old was also beset by soft tissue injuries at his former club Essendon, where he managed 33 games in three seasons before crossing to the Power at the end of the 2020 campaign.

Port's football manager Chris Davies says medicos "don't have clarity" on just how long Fantasia will be sidelined by his latest injury.

"We will keep searching for answers," Davies told reporters on Monday.

"We will leave no stone unturned to try to get him the right care to get him back playing.

"The past 36 hours for him have not been great but I know he has a commitment to start his rehab again.

"And all we can do is provide him with an environment where he can get back to full fitness and get back playing."

Fantasia was on the cusp of returning three weeks ago but reported thigh soreness.

"He had a setback three weeks ago (when) we thought he was ready to go," Davies said.

"This time, it's slightly worse than that.

"He has had a massively interrupted pre-season, there's no doubt we are going to need to put some load into him before he gets back at SANFL or AFL level."