Fremantle Dockers coach Justin Longmuir surprised many with his candid assessment of his team's performance following an emphatic 51-point win over Richmond.

Despite the comprehensive victory, Longmuir was rather frustrated, grading the team's effort with an unconvincing pass-mark.

Longmuir's post-match comments were unexpected given the Dockers' relatively dominant display at Optus Stadium.

He remarked: "we had some good moments and some things that were a little bit frustrating."

"I thought we played to probably a seven out of 10.

"The second quarter was frustrating. I thought we were unpredictable. Especially our intent to pressure dropped off. But we stuck at it.

"To win by 51 points, you don't want to be Debbie Downer. I just think we've got so much improvement left in us."

The win, which saw Fremantle triumph 16.9 (105) to 7.12 (54), featured standout performances from several key players.

Josh Treacy kicked a career-high five goals, Andrew Brayshaw was instrumental in the midfield, amassing 35 disposals, six clearances, and a goal.

Hayden Young also impressed with 24 disposals, two goals, and 10 score involvements, continuing his red-hot form as a mid-forward presence.

Despite his frustration, Longmuir did acknowledge the positive aspects of the game.

"I think our best tonight was very good. And then some of the mistakes we made and the unpredictability - it just took a little bit of gloss off it for the way we want to play."

"To win by (51) points you don't want to be a Debbie Downer, but I just think we've got so much improvement left in us.

Fremantle's victory solidifies their position as genuine top-four contenders, still sitting third on the ladder as potential premiership contenders, especially having knocked off clear flag favourites Sydney at the SCG.

Longmuir still wants more consistency as his side prepare for the upcoming challenges at the business end of the season, including a tricky test against Hawthorn in Launceston.

They will be without ruckman Sean Darcy, who suffered a concussion, and defender Josh Draper, who is in doubt with a corked leg.

PERTH, AUSTRALIA - MAY 20: Sean Darcy of the Dockers celebrates a goal during the round 10 AFL match between Walyalup/Fremantle Dockers and Geelong Cats at Optus Stadium, on May 20, 2023, in Perth, Australia. (Photo by Paul Kane/Getty Images)

Brennan Cox's return to the backline was a highlight for Longmuir, who said "he's got to build with his fitness and play larger game time, but I thought he looked pretty sharp."

"There's probably a couple of contests where he could have imposed himself in a different way and looked a bit rusty. But largely I thought his return was pretty sharp.โ€