The 20-year-old man mountain became the first NRL forward drafted when picked up by reigning Super Bowl champions the Philadelphia Eagles on the weekend.

And he has a fan in former South Sydney premiership coach Maguire, who watched him steamroll would-be defenders in the under-20s Rabbitohs last season.

"He walked into the club, the world's biggest bloke I've ever seen, and I thought 'what do I have here'," Maguire recalled on Fox League's NRL 360.

"He weighed about 166kg ... stuck his hand out and say 'g'day Madge' and thought 'wow this is an impressive kid'.

"I thought he was 26, 28, but he was 19 years old."

The 203cm, 160-kilogram wrecking ball opted to pursue his NFL dream rather than a spot on the Rabbitohs' roster this season and Maguire thinks it was a no-brainer.

"The first thing I said was that he'd have to lose a bit of weight to play our game and he went from 166kg to 140kg," he told NRL 360.

"Rugby league, being a fairly aerobic game, with an anaerobic aspect, wasn't the best game for him.

"He's been able to find a game now that could take him, and really put Australia on the map again."

Mailata faces a steep learning curve in order to make the Eagles' final 53-man roster but Maguire says he has the skills to succeed.

"I've been lucky enough through the years to spend a bit of time around NFL teams including the New York Giants and Jets, the Eagles, the Seattle Seahawks and Atlanta Falcons," the NRL premiership-winning coach told Players Voice.

"I've seen the type of athletes that thrive in that sport. Jordan ticks a lot of those boxes.

"He's huge, obviously, but he's also explosive out of the blocks and agile for a man his size."

Australian Associated Press