PHILADELPHIA (973espn.com) - The only thing bigger than the 6-foot-8, 350-pound Jordan Mailata may be the learning curve he faces in trying to make the transition from Australian rugby bruiser to NFL offensive tackle.

From a physical standpoint, the Eagles' seventh-round pick is straight out of central casting when it comes to an NFL offensive tackle right down to his lengthy 35 1/2 arms which could have opposing pass rushers orbiting the earth before they can get to the quarterback.

Playing in the NFL is about more than prototypical size or outstanding athleticism, however. If that were the only hurdle, every Olympic sprinter would be making millions as an NFL wideout and Mark Henry would have been engulfing double teams as an NFL nose tackle rather than slamming people in a WWE ring.

Mailata isn't the trailblazer when it comes to the leap from the Australian rugby world to the NFL. That title belongs to former San Francisco fullback Jarryd Hayne, who spent eight games on the Niners' 53-man roster in 2015 before making a return to the National Rugby League down under.

With Mailata trying to make a similar jump NRL.com caught up with Hayne, who explained some of the difficulties Mailata will have, starting with a piece of equipment. In rugby, there are no helmets.

“He needs to get used to the helmet obviously because offensive linemen have to do a lot of non-verbal communication where you can’t speak to the guy next to you," Hayne explained. "You’ve got to be able to signal him, you’ve got to be on the same page. For example, the quarterback might change the blocking scheme or the defense might rotate in an instance, just little things like that. The helmet does hinder your vision but you’ve got to really get used to it in order to see how everyone is moving, and the rotations.”

An even bigger issue -- especially with a coach like Doug Pederson -- will be the depth of the playbook, according to Hayne.

“You can go into the NFL and understand a little bit of what you’re going to learn, but until you sit down in a room and see the playbook, the defensive schemes, it just blows your mind,” Hayne said. ”I went in there with some idea, like ‘oh yeah, I kind of get it’ but not only do you have to learn all the schemes, but you also change them every week. And it’s not one of those things where you get time to learn and change them; it’s like ‘BOOM we’re doing this now’ and you’re expected to know it.”

The odds are long for Mailata to make such a difficult transition but the Eagles felt his rare size and athleticism was worth the try.

The likely path would be a year on the practice squad before making a run at a roster spot in 2019.

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen