Fremantle captain Nathan Fyfe has heaped praise on youngster Brennan Cox, saying he is the club’s number one key defender heading into the new season.

Injuries to Alex Pearce and Joel Hamling opened the door for Cox who now looks cemented down back for the Dockers after starting his career as a forward.

Moving the 22-year-old into defence has proven a masterstroke by coach Justin Longmuir with Freo’s defensive record stacking up as one of the best in the competition last year.

“Cox has trained really well across the summer — had his best off-season to date and he looks to be our number one key defender at the moment,” Fyfe told Sportsday.

“He reads the ball in the air as well as any defender that I’ve played against. And we’ve done a bit together in match simulation.

“And ‘Coxy’ knows what he’s capable of, I think his best mate Luke Ryan getting an All-Australian nod last year has really opened up the possibilities for his own career and where he could possibly go.

“We’ve seen it in his training with his application. He’s a different cat. The group absolutely love the way he brings the energy on-field.

“But with his training standards, we’re hopeful now he sees himself as being one of the best defenders in the comp and hopefully he can string together that sort of a season.”

A selection headache looms for Longmuir if Cox, Pearce, Hamling and Griffin Logue are all fit, but Fyfe doubts they’ll be available at the same time.

“If all four of them are up and running it’s a great headache for (Justin) Longmuir and the match committee to have,” the dual Brownlow Medallist said.

“But I’m just not confident that all four of them will be firing at the same time, but who knows.”

Pearce and Hamling both missed all of 2020 with respective ankle injuries, but are pushing to play in Fremantle’s season-opener against Melbourne at the MCG.