Throughout every game of the preseason, everywhere Indianapolis Colts coach Chuck Pagano went, Daniel Adongo followed. A 6-foot-5, 257-pound South African rugby-player-turned-linebacker, Adongo didn't know a lick about football. As Pagano said: "First time ever putting on a helmet, No. 1. Then pants, No. 2. Shoulder pads, 3."

"It is very exciting," Adongo said, his English reflecting the cadence of his native Kenya. "The hairs on the back of my neck stand up every time we go out. To see the preparation become real game play, it's so inspiring. I want to be out there so badly."

Daniel Adongo is new to American football, but the former rugby player's physique intrigues the Colts. Lee Warren/Gallo Images/Getty Images

Longtime scout Jon Shaw had lobbied the Colts' front office to invite Adongo to camp because of his raw athletic ability. Skeptics were silenced when the 23-year-old showed up, fresh off a plane from Johannesburg, and broad-jumped 11 feet, which would have been sixth-best at this year's combine. Not bad for someone who'd never broad-jumped before.

Adongo ended up snagging one of Indianapolis' eight practice-squad spots despite not recording any preseason stats. "He's a clean canvas," Colts linebackers coach Jeff FitzGerald said.

The league seems to be stocking up on such canvases. A record 12 foreign-born players were selected in April's NFL draft. From 1990 to 2011, only seven players who didn't attend high school in North America were drafted. In the last two drafts, there have been five. Those foreign-born players bring varying levels of football experience. Certainly none has the typical U.S. background of pee-wee leagues, Friday night high school games, year-round television exposure, and endless coverage of major college football and the NFL.

Ezekiel "Ziggy" Ansah, whom the Detroit Lions drafted No. 5, came to BYU from Ghana hoping to play basketball. He ended up on the track team, where teammates and coaches coaxed the 6-foot-5, 275-pounder into trying football. After less than one year as a starter, he became the only top-five pick since 1990 with no high school football experience.

At BYU, the affable Ansah quickly developed a sort of Paul Bunyan persona, blowing up kickoffs in practice and wrecking weight rooms. "When he got to BYU, he'd never lifted a weight in his life," college teammate Romney Fuga told ESPN The Magazine in April. "But we'd all seen him with his shirt off. Suddenly we realize, 'Wait -- all of this is just DNA?'" After sitting out much of the NFL preseason with a concussion, the defensive end recorded his first half-sack in Week 1 against the Vikings. He looked even more comfortable last weekend against the Cardinals, playing 50 snaps and consistently drawing double-teams. With two quarterback hits and one hurry, Ansah graded out as the Lions' second-best defender against Arizona, according to Pro Football Focus' metrics. If all goes to plan, it will be the first of many impact games for the 24-year-old.

Ezekiel Ansah, who was born in Ghana, recorded a half-sack in the Lions' opener against the Vikings. Andrew Weber/USA TODAY Sports

Margus Hunt also came to the United States with non-football dreams. He relocated from Estonia to Dallas to work with SMU track and field coach Dave Wollman, who then sent the 6-foot-8, 280-pound discus/hammer/shot-put thrower to see Mustangs football coach June Jones. When Wollman predicted that his former protégé would run a 4.6 40 at the combine, some laughed. Then Hunt ran a 4.51, the fastest 40 time of all front-seven players this year, along with 38 bench-press reps and a vertical leap of 34.5 inches.

Now Hunt, a second-round pick in the draft, is a rookie defensive end in Cincinnati and a star of HBO's "Hard Knocks." Viewers saw teammates compare him to Ivan Drago of "Rocky IV" and coaches liken him to J.J. Watt. Former Pro Bowl defensive end Greg Ellis, a visiting guest at Bengals practices this summer, went as far as to tell the newbie that he has the potential to become a $100 million player.

"You might think a situation with a guy that has so little experience would be complicated, but it's the total opposite," said Jones, who coached in the NFL for more than a decade. "What you find is an eagerness to learn and a total absence of bad football habits to undo. Heck, they have no football habits at all. And when an athlete just makes your jaw drop to the floor like that, the risks are worth the potential reward."

Those risks vary in direct correlation to the player's level of experience. The four 2013 draftees who attended non-North American high schools but went to U.S. colleges (Ansah, Hunt, Raiders offensive tackle Menelik Watson and Seahawks defensive tackle Jesse Williams) received contracts totaling $23.3 million guaranteed. Adongo, on the other hand, hopes eventually to make a base rookie salary of $405,000, but now he receives the practice-squad minimum of $6,000 per week. That's a comparative pittance. And those relatively small payments are part of the reason NFL front offices are beginning to explore the next frontier in international scouting.

Oakland OT Menelik Watson was born in England and played at Florida State. AP Photo/Stephen Brashear

The gold standard in international talent -- the prototype for what scouts are looking for -- has to be Patriots offensive tackle Sebastian Vollmer. Born in Germany, Vollmer didn't play football until he was 14. Despite a solid four years at the University of Houston, Vollmer wasn't invited to the 2009 combine. Still, Bill Belichick & Co. saw something in Vollmer, reaching for him at the end of the second round of that year's draft. He was an All-Pro by his second year and signed a four-year, $27 million deal this past offseason. By most standards, Vollmer is in the conversation as one of the game's best linemen. Not bad for a guy who barely spoke English as a college freshman.

"You've seen in other sports, this wide net cast all around the world," said former NFL general manager Bill Polian, now an analyst for ESPN. "It was inevitable with football, but there are challenges that baseball or basketball doesn't have."

Chief among them: Football is still largely a U.S. sport. Although leagues such as the defunct NFL Europe and other international outreach programs have opened eyes to the game, it still isn't widely played.

Sometimes athletes take to it immediately. That was the case for Bjoern Werner, the Colts' German-born rookie linebacker. He came to the U.S. from Berlin as part of a student-exchange program in the fall of 2007. While living in Salisbury, Conn., Werner fell in love with football and continued to pursue roster spots on club teams after returning home. Eventually, he came back to the United States and became an All-American at Florida State. Now he's a teammate of Adongo's with the Colts, and the end-turned-linebacker has one sack and three quarterback hurries through Week 2, according to Pro Football Focus.

Werner's teammate at Florida State, Watson, may have picked up the game even faster. Watson made the trip from England to the U.S. to play basketball for Marist College. After flaming out as a hoops player, he became intrigued watching American football on TV. He eventually transferred to Saddleback College in California to try his hand at juco football. At 6-foot-5 and 300 pounds, Watson quickly showed the raw ability to play offensive line, and within a year he had transferred to Florida State and was starting on the opposite side of the ball from Werner. Despite only one season of high-level football, the Raiders loved what they saw from Watson and grabbed him with the No. 42 overall pick in the draft. Until a knee injury sidelined him for the season's first month, Watson was Oakland's projected starter at left tackle.

The Texans' fourth-round pick, linebacker Trevardo Williams, moved from Jamaica to Connecticut in 1999 and eventually landed at UConn, the only major college to offer him a scholarship. After a productive college career, Williams had jaws dragging at this year's combine, where his 4.57 40-yard dash beat the times of top running back prospects Le'Veon Bell and Joseph Randle. The big question marks with Williams, as with many of the international prospects, revolved around experience playing against high-level opposition. But this preseason, Williams had coaches raving with a team-best 3½ sacks before an ankle injury landed him on injured reserve.

The complexity of the Bengals playbook can sometimes be difficult, says Estonia native Margus Hunt. AP Photo/Joe Robbins

With other players, though, the amount of football data, especially the NFL playbook, can be overwhelming, as it has often been for Hunt.

"I have been there, a lot," Hunt said during the preseason. "But the more I know, the more I am comfortable with it. I feel like I can play faster and shut my brain down and do what I've been taught. Subconsciously, I am thinking too much about not trying to make a mistake, and that isn't good for anyone."

Of course, the willingness of NFL teams to fish for projects isn't just limited to overseas. In the 2011 draft, the Broncos selected little-known Portland State tight end Julius Thomas in the fourth round. After emerging as a record-setting power forward at the school, Thomas walked into the football coaches' offices and asked to walk on. At 6-foot-5 and 240 pounds, and with the quickness to be an all-conference college basketball player, Thomas certainly had the frame, so the coaches gave him a shot. Thomas hadn't played football since middle school.

Fast-forward three years, and Thomas looks like an Antonio Gates-type breakout star for the Broncos, who hadn't had a 100-yard game from a tight end in three years until Thomas hung 110 yards on the Ravens in the season opener. After being nagged by injuries last year, Thomas looks like an emerging favorite target for Peyton Manning and is a good example of why scouts now say football experience is secondary to athletic ability and smarts.

"I was watching the original 'King Kong' the other day on TV, and that movie director needed an actress for his film, but no one would take the part," one NFL scout said, promising his story had a point. "He was desperate. In the end, he just rode around New York and found a girl that looked right for the role and said, 'Hell, I can teach her how to act.' That's it. You find a guy who looks the part and hope he knows about football. If they don't, teach it, man. Make them love it. That's the push."

Broncos tight end Julius Thomas is showing that exceptional physical tools can make up for the lack of a long background in football. AP Photo/Joe Mahoney

Adongo's invitation to Indy was the result of such a push. After Colts general manager Ryan Grigson charged Shaw with the task of becoming "a pseudo-international scout," Shaw sifted through a pile of tapes that resembled an old "Wide World of Sports" library, looking for the obvious -- big, fast and strong -- but also the subtle, such as age, education, attitude and the ability to speak English. Adongo arrived off the Johannesburg rugby pitch with all the above.

"The most difficult part of a project like these guys are is patience," says Lions head coach Jim Schwartz, speaking of Ansah but echoing the words of Pagano on Adongo. "I'm not going to put a guy who is still learning the game in a situation where he's going to get hurt. If you take your time and develop them right, when they are out there full time, then we'll see the payoff."

So far, so good for Ansah. In his first preseason game, he made a jaw-dropping pick-six against the Jets that put his ridiculous athletic ability on full display … along with his inexperience. "When I caught it, I was like, 'Oh wait, the ball is in my hands, I got to go that way,' and I just did," Ansah said afterward.

Multiple busts could quickly turn a trend into fad. But what if the international players, most of whom are defensive linemen, start taking down quarterbacks on a regular basis? "Then this group right here," said an NFL scout, motioning to a row of colleagues at a college football game, "we're gonna need to get our passports renewed and start downloading some Rosetta Stone."