Fremantle senior coach Justin Longmuir believes Brennan Cox is one of the most underrated key defenders in the competition after restricting Coleman Medal leader Ben King to just one goal for the afternoon.

Speaking in his post-match media conference, Longmuir was full of praise for the defender.

“Brennan Cox is probably the most underrated key back in the comp and probably has been for a while,” Longmuir said.

“Not only was he able to negate King, but I thought he was able to win the ball back a lot, especially in that last quarter.

“The backs are working really well together, but they're getting good support from up the ground as well.”

King finished the day with seven disposals, one mark, one goal and a player rating of 0.5, according to Champion Data.

With the dubbed 'three-headed monster' not hitting the scoreboard in the win as it has in other weeks, it was hard-working forward Michael Frederick who enjoyed an equal career-high four goals on the day.

“You always want multiple avenues to goal, don't you?” Longmuir said.

“I think our tall forwards have got a lot of credit over the course of the year, and rightly so, but our small forwards have done a power of work and maybe haven't impacted the scoreboard as much, but they've impacted games a lot.

“It was good to see Freddy get some reward for effort. He clearly finished his work when others on both teams weren't, and he's embraced his multiple roles as well.

“He's playing on the wing a little bit more, and I'm really proud and really pleased for him.”

Fremantle will now travel to Canberra to take on GWS on Saturday 4 July, at Corroboree Group Oval.