Joon Yeo walked slowly toward the line of scrimmage, eyes resting on the unassuming defender in front of him. For weeks, the Westfield High School offensive lineman had been preparing for his debut on the freshman football team. Now that the time had arrived, Yeo was determined to make a good first impression.

“Hi, I’m Joon,” he said with a straight face, his right hand extended to a W.T. Woodson defensive lineman. “How are you?”

While the rest of the Woodson defense tried to figure out if this was a joke, Yeo’s incredulous teammates yelled for him to get down into his stance.

“When we came back in the huddle, we were all like, ‘Joon, what was that? Don’t talk to them!’ ” said offensive lineman Jason Beylor, recalling the October 2009 game. “Football was his first team sport, so he had no idea what he had done wrong.”

The unwritten rules of sports — let alone the rules of American football — weren’t a part of Yeo’s life growing up in South Korea. Before moving to the United States at age 7, Yeo (pronounced “yuh”) had never even heard of football. And when his friends coaxed him to join the freshman team at the Fairfax County school, Yeo wasn’t too keen on the idea of hitting people.

“Football was this violent, mean sport and I still felt bad sometimes when I hit people,” Yeo said. “The coaches had talked about good sportsmanship, but I didn’t know about when you should and shouldn’t do it.”

It would take three years of patient practice, sudden growth spurts and plenty of teaching for Yeo to reach the point he’s at today. Now a senior, he’s one of the leaders for the fourth-ranked Bulldogs, who will be trying to complete a second consecutive undefeated regular season Friday at Herndon. The 6-foot-3, 330-pound Yeo is also a legitimate recruit, with interest from schools such as Brigham Young and Temple.

Steep learning curve

As the United States celebrated its independence on July 4, 2002, the Yeos marked the start of their transition from Korea. Yeo’s dad, Chang Wook, had always wanted to move his wife and two sons here, but it wasn’t until he became a mechanic that the door opened for him to get a visa.

As 7-year-old Joon walked through the airport that day, the culture shock was immediate.

“Seeing other races of people was something I had not experienced because in Korea, you pretty much only see Asians,” Yeo said. “So when I came here and saw whites, blacks, Native Americans, Indians, it was really new to me.”

Just as new was football. Throughout middle school, a puzzled Yeo would listen as his friends passionately talked about the Redskins, leading him to check out a few games on television with his family. Although Yeo was far from impressed by the sport, his parents began to think the gridiron was a logical landing spot for their son, who by the age of 13 was already 5-10 and 200 pounds.

“At the end of middle school, all of our church friends kept saying it would be a good thing for him to try football,” Chang Wook said through an interpreter, his youngest son, Joon Kyung. “We didn’t know much about football, but we saw how big he was, and you don’t normally see Asians as big as him, so we thought he should try it and see if he liked it.”

It took one practice for Yeo to fall in love with football and two practices to realize how steep of a learning curve existed.

Often, Yeo would take instruction too literally. Yeo recounted one exchange when he missed a block on a blitzing linebacker in practice.

“Joon, you let the linebacker blitz right past you!” one of the coaches yelled.

“Um, what’s a linebacker?” Yeo innocently asked.

“The guy that just ran by you and hit our running back,” the coach responded.

“Oh,” Yeo said with a pause. “I thought you could only hit one person on a play, so I just let him go. Sorry.”

Conversations like that rarely happen on the football field at Westfield, a school with more than 2,800 students. The powerhouse football team won state titles in 2003 and 2007 and has two graduates currently playing in the NFL — San Diego Chargers wide receiver Eddie Royal and Washington Redskins tailback Evan Royster.

Yet for as mad as the coaches wanted to be at Yeo, they couldn’t help but appreciate his willingness to learn.

“It took some extra explaining, especially when it comes to football terms and slang,” offensive line coach Dan Keating said. “But he would pick up things pretty quickly so that once his fundamentals started to catch up with his size, you could see him really turning the corner.”

Realizing his potential

Yeo’s body seemed to grow as quickly as his football knowledge. Along with lifting weights for the first time in his life, Yeo exchanged his family’s traditional rice-based meals for more protein-heavy foods like chicken. By his junior year, Yeo had sprouted five inches and put on more than 100 pounds.

“Because of him, I basically live in the kitchen,” his mom, Nam Hee, joked in Korean.

It was around this time that Yeo realized football could be more than a hobby for him.

“He called me up one day his junior year and said, ‘Coach, do you think I could play football in college,’ ” Keating said. “It kind of took me aback because I was thinking, ‘Uh, Joon, have you looked in the mirror lately?’ ”

Of course he had, but aside from former Pittsburgh Steeler Hines Ward, who was born in Seoul to a Korean mother and African-American father, Yeo hadn’t seen examples of Koreans playing football. This notion was only confirmed during his family’s recent visits to South Korea, where his friends took little interest in the sport he played and strangers stared in awe at Yeo’s imposing frame.

“The only time I really see other Koreans playing sometimes is at other high schools teams around here,” Yeo said. “So since I’m a Colts fan, I’ve used Jeff Saturday as somebody I look at in the NFL to get tips.” Saturday spent 13 years as a center with Indianapolis before signing in March with the Green Bay Packers.

Based on Yeo’s performance during the past two years, it’s clear he’s been paying attention. After serving as the lone junior on Westfield’s senior-laden offensive line last season, Yeo now anchors a unit that’s helped the Bulldogs average more than 278 rushing yards per game and earn the top seed Virginia AAA Northern Region Division 6 playoffs.

Yeo’s evolution as a player is far from over. He still readily admits that he doesn’t know the difference between blocking a cornerback and a safety, and Keating had to get on him earlier this season for helping up an opponent during a play. Yet it’s that dichotomy – the aggressive student vs. the gentle giant — that’s gradually introduced Yeo to his immense potential as an offensive lineman.

“He says there are a lot of myths out there about him, but he was definitely clueless at first,” Westfield senior offensive lineman Ned Johnson said. “He doesn’t always like when we bring up the clueless stories, but in a way, his story and the way he plays helps bring glory to a position that doesn’t get much attention.”

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