Offensive line coach Paul Dunn couldn't figure out what in the world Jordan Mailata was doing by the Gatorade cooler.

It was their first day of on-field training at IMG Academy and Dunn had just finished putting the monstrous former rugby leaguer and another international player through a basic agility drill. Normally the exercise would have taken two minutes, but because of the students' lack of football experience, it dragged on for a half-hour under the Florida sun.

When the drill mercifully ended, the players -- dressed in helmets and full pads for the first time -- went to the sideline for what was supposed to be a quick drink break. Instead, they lingered by the hydration station, acting perplexed.

"They got their paper cup and they poured their Gatorade into the cup, and they both stood there for a good minute. I'm about a hundred yards away from them and I'm like, 'What are these guys doing?' After about a minute of standing there looking at one another, they both tried to drink the Gatorade through their helmet, and literally splashed it all over themselves," Dunn said with a laugh.

"A coach comes running over and he says, 'Mates! Mates! That's not what you do. You've got to take your helmet off!' Well, I'll tell you what, they didn't know how to put a helmet on, let alone take a helmet off."

That was Jan. 15 of this year. Just three and a half months later, on April 28, the Super Bowl champion Philadelphia Eagles traded up to select Mailata in the seventh round of the NFL draft to play offensive tackle. To bridge the divide, the time in between was dedicated to an intense crash course aimed at getting a 21-year-old who admittedly knew "as little as peanuts" about football NFL-ready in 15 weeks.

'One of the largest human beings I've ever seen'

A quick look at Mailata's rugby highlights with the South Sydney Rabbitohs Under-20s is enough to understand why Mailata piqued the NFL's interest. He stands 6-foot-8 and weighs 346 pounds. He's lean and powerful and moves with an agility and athleticism rarely seen in men his size. The rugby league mortals tasked with cutting down the nimble giant stood no chance, bouncing off his tree-trunk legs before hitting the turf with a splat.

"That was impressive," said Eagles vice president of player personnel Joe Douglas. "That definitely was an eye-opener, watching the YouTube [videos]."

Mailata's IMG Training Schedule 6:30-8 a.m. -- Breakfast/nutrition coaching

8-9 a.m. -- NFL team meeting/athletic training/ corrective exercises

9-9:30 a.m. -- Pre-Gen program to activate body

9:30-10:30 a.m. -- Movement training (combine prep)

11-noon -- Weight training

Noon-1 p.m. -- Lunch

1:1:45 p.m. -- Film/classroom work with coaches.

2-3:30 p.m. -- Field work

4-5 p.m. -- Recovery

5-6 p.m. -- Mental/media/vision training/yoga

6-6:30 p.m. Dinner/nutrition

It caught the attention of someone in the NFL's International Player Pathway program as well. Following a workout in Los Angeles, Mailata was picked to train at IMG Academy along with a select group of overseas players with the goal of securing one of the four NFL practice-squad spots designated for international prospects. The notion of getting drafted seemed to be a pipe dream.

But two things were immediately clear upon arrival at the facility in Bradenton, Florida. The first was that Mailata was a physical freak.

"Well, let's see, the guy is probably one of the largest human beings I've ever seen in my life," said IMG's strength and conditioning coach, Jay Butler, when asked about his first impression of the Aussie. Butler was the Tampa Bay Buccaneers strength coach for two years. He said Bucs players in Mailata's weight range tended to have around 30 percent body fat; Mailata's was around 17 percent by the end of training.

"In my years of coaching, I probably haven't had anybody who looks like that, top to bottom," he said.

The players were given Beach Cruiser bikes to get from one side of campus to the other. The staff got a kick out of the lighthearted Mailata -- known to break into song or dance at any moment during the course of the grueling days -- toying around on what he made seem like a kid's bike.

"He just looked kind of silly on this beach bike because he's so massive, riding around like the Wicked Witch of the West in 'The Wizard of Oz,'" Butler joked, "so we'd have fun with him."

The second thing that jumped off the page was his lack of football knowledge. According to Dunn, Mailata didn't know a first down from a touchdown when he arrived on campus.

"I remember the first day Jordan came in and we were doing their intros, and I was like, ‘What's your favorite team?' and he just kind of didn't know anything. It was literally shocking," said Taryn Morgan, the assistant director of athletic and personal development at IMG. "He probably couldn't have even told us a team [in the NFL] at that point, or who his favorite player was. He had no idea. It was so endearing."

But there was a lot of work to do. Mailata had to learn a new sport while simultaneously preparing his body for combine-like testing for his upcoming pro day, which then was just over two months away. To meet those rather insane demands, he was immersed in a jam-packed holistic development program that went from sunup to sundown and included movement and strength training, on-field and classroom work, nutrition, mental and vision training, and leadership and media instruction.

From Rugby To The NFL The Patriots' Nate Ebner has been the most successful athlete to jump from rugby to the NFL, but he's not the only one who tried. Here are a few others and how they fared, according to ESPN Stats & Info: Jarryd Hayne, RB, San Francisco 49ers, 2015 He was signed as an undrafted free agent after playing for the Fijian and Australian national rugby league teams. After rushing for 175 yards on 15 carries in the preseason, he rushed 17 times for 52 yards and caught six passes for 27 yards during the regular season. He also played for Fiji's Sevens rugby team after leaving the NFL. Hayden Smith, TE, New York Jets, 2012 He was signed as an undrafted free agent after playing for the United States national rugby team. He had one catch for 16 yards. He also played for the Saracens club in England. Some other notable rugby players who played in the NFL, but also played college football: David Dixon, OL, Minnesota Vikings, 1994-2004 He played rugby and football at Arizona State and started 134 games for the Vikings, mostly at right guard. Colin Scotts, DT, St. Louis Cardinals, 1987 He was offered a football scholarship by Hawaii while playing for an Australian Schoolboys team on a tour. He had two sacks in seven games. Paul Lasike, FB, Chicago Bears, 2016 He played football and rugby at BYU after growing up in Australia. He rushed three times for eight yards in 10 games, including three starts for the Bears. He played primarily on special teams. Ebner, DB, New England Patriots, 2012-present He was a second-team All-Pro in 2016. He played rugby and football at Ohio State and was drafted by the Patriots in the sixth round in 2012. He represented the U.S. at the 2016 Rio Games.

The work spilled into nights and weekends. Mailata shuffled (or cruised) from one station to the next. One minute he'd be working on his 40-time get-off, the next he was in the classroom learning about zone schemes, defensive fronts and trap pulls. He'd go from on-field training -- Mailata practiced with high school seniors at the academy as he learned to function in his new ecosystem -- to the "mind gym," where he'd pop on 3D glasses for some cognitive training to enhance things like reaction time.

"The last three or four months have not been easy," Mailata said on the night he was drafted, "mentally challenging as well as physically."

He quickly began to see results, however. Even though strength gain was not a major focus in the lead-up to his pro day, his bench press went from around 16 reps of 225 pounds to 25 reps, according to Butler, while his squat numbers shot up from around 400 pounds to 500 pounds. And his body-fat percentage shrunk from 22 percent to 17 percent.

"The physical shock was awesome. The first four weeks he was dying, just dying every day. And it was like, 'Nope, nope, that was the warm-up,'" said Steffen Visk, assistant head of physical conditioning.

"[The body change] was drastic. You could tell that he's never been in an intensive environment where your full-time job is to work out. You're training 30 to 35 hours per week, and when you're not training, you're doing things to help you recover so that you can train more. ... You could see the fat melt, the muscle start to build up, you see the core strength. It was very, very awesome."

Significant strides were made in the football realm as well. Mailata recently joked that he knows as much as "two peanuts" now, signaling just how much learning he still has in front of him despite his advancements. According to Dunn, Mailata now has an understanding of football language and how to apply it.

"He's just grown leaps and bounds," Dunn said.

His development caught some evaluators off guard during his private pro-day workout at IMG in April, which was run by Eagles offensive line coach Jeff Stoutland.

"I don't know if Jeff thought, ‘Why are they sending me on this mission for this guy that has never played football before?' But I've been in this a long time and have conducted myself many, many pro individual workouts, and if there was one that was better, I can't remember," Dunn said. "And I worked a lot of All-Pro offensive linemen out and none of them held a stick to this guy. He was just incredible. I think that opened some eyes."

Mailata ran a 5.12-second 40-yard dash, which would have ranked eighth among offensive linemen at the combine. His strong performance at his pro day led to a higher level of interest. Seven teams brought him in for a visit: the Eagles, Washington Redskins, Cleveland Browns, Los Angeles Chargers, Atlanta Falcons, Indianapolis Colts and New York Jets. Philly was the one that grabbed him, moving up 17 spots in the seventh round to do so.

Getting acclimated to the NFL

"Don't pause! This is the National Football League. You ain't got no time to pause!" Stoutland shouted at Mailata on the first day of Eagles rookie camp. "Go ... Go! Good."

Stoutland poured lots of energy into his new pupil during the session, teaching him how to stay low in his stance and guiding him through basic individual drills. Mailata said he felt like Stoutland was challenging his manhood during his pro-day workout back in April. Judging by their early interactions in Philly, the gruff offensive line coach is going to keep the heat turned up.

Eagles offensive line coach Jeff Stoutland has been tough on Jordan Mailata, but the former rugby star appreciates the focus and dedication. AP Photo/Chris Szagola)

"I love him. He's a great coach," Mailata said. "I guess he just gets frustrated when he sees potential and I'm not fulfilling it. So I just need to keep my head in the books."

Asked how overwhelming all this is -- taking on the challenges of being a professional football player despite being brand new to the sport -- Mailata said, "You can't put it on a scale; that's how overwhelming it is. There's so many things that you have to think about and weigh up. Overwhelming? That's gone out the window."

He joked that he'd have to buy dinner for the rest of the linemen that night just so he could pick their brains, and said the rest of the night would be spent in his hotel room studying his assignments. He plans to lean heavily on Jason Peters, Lane Johnson and the rest of the veteran group as he gains his footing.

Because of the of talent and depth in that offensive line room, the Eagles had the luxury of investing in Mailata, who will clearly need more seasoning before he's ready for game action -- if he's ever ready. In their view, he's like a piece of clay -- a 6-foot-8, 346-pound, athletically loaded piece of clay -- who already has shown a willingness to be molded.

"You can't put it on a scale; that's how overwhelming it is. There's so many things that you have to think about and weigh up. Overwhelming? That's gone out the window."

"I don't see him having the learning part of it slow him down one bit. He's ready. He's ready to roll," Dunn said. "What I see him having a time span with is just repetitions. It's just continuing to do things that other guys have done their whole life, and he's doing for the first time. That's going to be the tricky part.

"I think what will slow him down is just the fact of doing football drills and then getting out there and playing the game. There's nothing that can prepare him for that other than experience."