FREMANTLE's annus horribilis has continued with emerging young defender Alex Pearce set to miss the rest of the season after breaking his leg during Saturday night's loss to Richmond.

Pearce landed horribly on his right leg in a marking contest in the last quarter of the 38-point loss at Domain Stadium.

His ankle appeared to turn badly and he could not put any weight through the leg after the incident.

He was carried off by the trainers and did not take any further part in the match.

WATCH: Ross Lyon's full post-match press conference

Fremantle coach Ross Lyon confirmed that the promising youngster had broken his tibia and would miss the rest of the season.

"We're really quite upset at the minute," Lyon said.

"It doesn't look great. It's a confirmed tibia. So it's broken. It will obviously be the season.

"It's really, really upsetting."

WATCH: Alex Pearce's injury against Richmond

Pearce, 20, was one of the few shining lights in the Dockers' dismal season so far. The third-year key defender won the Dockers' best young player award last season after playing 13 games and had progressed again this year. He kept Adelaide skipper Taylor Walker goalless in round six and held Greater Western Sydney star Jeremy Cameron to just one goal in round seven.

"It's really hard to find young tall defenders," Lyon said.

"A third-year player playing on keys, really holding his own and beating them in a team that's really been struggling, to be truthful. It's hard enough when you play in a good team.

"We'll wrap all our support around him. He'll have to work his way through it. It's not ideal, obviously, but we'll try and keep perspective and he'll bounce back at some point in the future but it's going to take some time."

Five talking points: Fremantle v Richmond

Pearce's name is added to the mounting list of serious injuries at the Dockers this season. Nat Fyfe (leg) and Harley Bennell (calf) have already been ruled out for the entire season. Aaron Sandilands (ribs) and Michael Johnson (knee/hamstring) have no return date set, having already missed significant portions of the year.

Lyon said Pearce's injury was just in keeping with a theme.

"It's sort of sitting in there with the way things are happening at the minute," Lyon said.

"Look, I can believe it. It's just our annus horribilis, isn't it? A terrible year."

The Dockers were also missing Stephen Hill against Richmond after he was ruled out with a tight adductor but he should be right to return against St Kilda next week.

Lyon did suggest that skipper David Mundy might have picked a minor calf problem during the Richmond loss that could leave him in doubt to face St Kilda next Saturday.

"He looks like he looks like he's got a bit of a calf strain, so he is probably unlikely for next week," Lyon said.

Mundy told reporters he was just a bit "battered and bruised" in the rooms but he has missed three home and away matches and two NAB Challenge matches this year with a calf injury.

Clancee Pearce was involved in a clash of heads with Richmond's Steven Morris in the final minutes of the game. He came off the ground looking groggy but Lyon felt he should be OK to front up next week.