COREY Adamson knew the transition from professional baseball to professional football would be a challenge, but he didn't think an AFL pre-season would be as hard as it has been.

The 22-year-old has been an interesting case study since he was plucked from left-field – literally – to be drafted as a rookie by West Coast last year.

He was an under-15 All Australian footballer and has loved the game since the age of five but six years of professional baseball in the United States left him unprepared for an AFL pre-season.

"I'm loving the experience," Adamson told AFL.com.au.

"But it's a whole lot of hard work. I got told it was going to be hard work, but I didn't think it was going to be like this. Just the amount of running we do every day is just completely different to anything I've ever done before really."

His body shape has changed significantly. He has lost seven kilos from his lower body, a crucial power source for baseballers, and his upper body shape is unrecognisable from six months ago.

"I feel like I've got a completely different body now," Adamson said.

"It doesn't feel or look like the same as it did before.

"There have been a couple of issues with that. Just getting sore and what not. But nothing major at all. Just the regular things coming from a sport where the most I would run would be 30m and then coming here and running 10-12kms a day."

Not that baseball is a walk in the park physically. Adamson's throwing shoulder still clicks when he rotates it, a legacy of playing nearly 300 days a year during a six-year professional career that took him all over the world.

But he wasn't leading the glamourous life of a major league player.

Despite being a member of the San Diego Padres organisation, he was playing in the minor leagues for a very low wage, so when West Coast came knocking with an offer to come back and play football in Australia, none of his teammates begrudged him the chance.

"They all loved it," Adamson said.

"Minor league baseball is a grind. You play 150 games in 155 days, so there's a lot of talk about guys wanting to do other things in minor league baseball … whether it's go back and play college football or go do something else.

"So when a positive opportunity arose for me, where it's going to be another professional sport and straight into a professional team, they all said, 'I think you should do it, go see what it's about and change it up a little bit'."

Despite numerous moments of doubt, Adamson said he felt part of a family already at West Coast compared to getting lost in the segregated machine of a major league club.

"It's completely divided," Adamson said.

"The major league team never has anything to do with the minor league team.

"When I got here that was what surprised me most – the first day I rolled out and I was training with all the boys I'd watched growing up, like Beau Waters. That was kind of surreal to me.

"But also with the Eagles I feel like I can form a relationship with everyone. From the top, the CEO down to all the players, even the physios, just everyone. It seems like a real family bond that we have here, which I love."

Adamson said he has no placed no ceiling on what he could achieve in 2015. He is being groomed for a role at half-back and has been given the mammoth task of playing on star forward Josh Kennedy in practice matches to accelerate his learning.

"Just relearning the game is a massive one for me," Adamson said.

"That's going to be my first priority.

"I'm going out there every day and I'm going to work to play in the AFL, but then in saying that I'm also realistic about my chances and knowing that I'm going to really have to perform well at East Perth level to be given a shot."