Fremantle coach Ross Lyon is confident big man Michael Apeness will overcome an injury-ravaged start to his career and fulfill his potential once he recovers from his latest knee setback.

Apeness, 22, is set for a PCL reconstruction next week and has been ruled out for the rest of the season after hurting his right knee during his WAFL comeback from a left knee problem on Saturday.

The 200cm tall has endured a horror run since he was drafted with pick No.17 in 2013 as a long-term replacement for Matthew Pavlich in attack.

Issues with both knees and a broken collarbone have played a part in restricting Apeness to just seven of a possible 63 games since his debut three years ago.

"It's disappointing for Michael, it's disappointing for us," Lyon said of Apeness' latest setback.

"It puts some pressure on your list, there's no doubt about it as a first-round pick from four years ago.

"You really want those guys to come through, so he'll get there in the end.

"It's just going to take some time."