FIRST-year Fremantle ruckman Jack Hannath has paid tribute to Aaron Sandilands after his emergence as a reliable big man for the injury-hit Dockers.

Fremantle swooped on Hannath in last year's pre-season draft after the SANFL ruckman had been training with Melbourne.

After getting over the shock of becoming a Docker, Hannath has made an immediate impression, playing six games this season as the Dockers ruck stocks have taken a battering courtesy of long-term injuries to Aaron Sandilands, Jon Griffin, and Kepler Bradley.

The 21-year-old mature age recruit from Central Districts made a big impact in his first game against Richmond in round five when the Dockers fell over the line by one point in a thriller at Patersons Stadium.

Hannath took a key mark in defence in the dying seconds to ensure Fremantle would claim the four points.

"It was a nice moment in your first AFL game at the top level to know that you can perform when you need to so it was a very exciting moment for me," he said.

He said one of the main elements of his improvement had been the opportunity to learn from three-time All Australian ruckman Sandilands.

"It's been great. I was glad in the pre-season I got picked up by Fremantle so I wouldn’t end up rucking against him at any stage because he was pretty strong during pre-season," he said.

"He's been a big help. Obviously you look at him with his credentials and his list of accomplishments - he's obviously someone who's a handy person to have to be able to pick their brains.

"He's been great to me. Even when I was playing WAFL and then when I got in the senior team, advice and going through vision with him has been good."

Hannath said he was shocked to be drafted to the Dockers while he was training with Melbourne in Darwin during the pre-season.

"It was a big shock," Hannath said on Wednesday.

"Obviously I hadn't seen it coming. I'd been training with Melbourne and hadn't heard much in the way of Fremantle and so to find out on the day of the draft was a big surprise."

Hannath had to leave Darwin immediately and make his way to Perth via Melbourne and Adelaide.

The 201cm ruckman used the time to get his head around the strange turn of events.

"I went back to Adelaide before heading over to Perth, by the time I was heading over to Perth I had my head wrapped around it," he said.

"Obviously while I thought I was going to Melbourne nothing was signed and sealed."

"By the time I got to Perth I was ecstatic to be at Fremantle."

Hannath doesn't feel as though it has been a blessing in disguise, given his opportunities at Fremantle and the struggles of Melbourne thus far this season.

"When I was at Melbourne for the couple of weeks I had a good time, it was a good experience," he said.

"Like most footy clubs, they had a lot of good people at their club and I got on well with a lot of the guys but … unfortunately they've struggled a fair bit on-field this season and have probably copped it a fair bit in the media as well which you obviously hear about.

"But in saying that I wouldn't say from that perspective it's a blessing."