LAKE BUENA VISTA, Fla. -- Ponder, for a moment, Tanner Mangum's predicament.
Just done with a senior season in which he threw for nearly 4,000 yards to validate his status among the best high school football players ever from Idaho, the 6-foot-2 quarterback finds himself this week surrounded by other emerging stars at the Under Amour All-America Game festivities.
They're all headed to elite college programs in 2012 -- a few as soon as next week.
Except Mangum.
Before he graduates this spring from Eagle High School northwest of Boise, Idaho, Mangum will be assigned a destination that will be home for the next two years. In September, while others here start the journey of a lifetime, Mangum will do the same -- an LDS mission.
It has been his ambition since Mangum was 12 and watched his brother, Parker, return from serving in Italy.
"It affected me," said Mangum, who plans to sign a letter of intent next month with Brigham Young and defer his enrollment to 2014. "That experience of serving others, I envied that."
Outsiders make many assumptions about Mangum -- that, as a Mormon, he is required to serve, or that his passion for football, somehow, cannot equal that of others who progress in the sport traditionally from high school to college and beyond.
Mangum showed his toughness by returning this year from a shoulder injury that cut short his junior season. He outshined nearly every QB nationally last summer at The Opening, and again in the Elite 11 finals, vaulting Mangum from relative obscurity into the ESPNU150.
Expect him to fare well in competition with more highly ranked QB prospects Jameis Winston and Zach Kline for the White Team's starting job in the Under Armour Game (7:30 p.m. ET Thursday on ESPN).
"He plans to be the guy," said Paul Peterson, Mangum's coach at Eagle High School. "Tanner does not lack for confidence."
And Mangum alone made the decision to serve a mission.
"No one is forcing him to go," said Tanner's mother, Karen Mangum. "He has a very mature perspective for a young man his age."
Mangum, as a missionary, will get two phone calls home per year -- on Mother's Day and Christmas. Otherwise, he expects his work to consume him, with little time to even think about football.
"People are surprised when I tell them I'm leaving," Mangum said. "They might assume that I'll lose the touch or come back rusty. But I worry only about what I feel in my heart."
So, in fact, this is no dilemma for Mangum. It's the fulfillment of a dream that brings perspective to his life. And just maybe, it's the secret to his success.
A 'tender' decision
Steve Young, the former BYU and seven-time Pro Bowl quarterback, understands Tanner Mangum.
Young's brothers Mike and Tom also played quarterback at BYU. Both interrupted their football careers to serve missions. Steve did not.
"I wish I could have," he said. "All of us have a desire. I had a huge desire for it. It was just a different time."
The issue of who serves and why he or she makes the choice, Young said, is "tender" and often misunderstood.
"I've been trying to fulfill a mission for 30 years," he said.
Young attends church in California with Karen Mangum's sister, Kelly, and her husband. The proud aunt and uncle have told him all about Tanner.
"You've got to understand," said Young, a member of the College and Pro Football Halls of Fame, "that he's seeing this and talking about it among his family like you would not expect. Football is definitely secondary. And I think it's wonderful.
"This is a big part of our culture. We're 100 percent behind him and completely understand."
There's another side to it, though, Young said. When Mangum completes his mission and begins school at BYU just shy of his 21st birthday, he'll need time to reassimilate to being the kid who this week is zipping passes with perfection among his peers.
"It's tough, physically, to take two years off and get back in shape," Young said. "The guys who are successful at it put the time in, because that's not an easy transition. There are many challenges, most of them are physical."
It's a gamble in football, no doubt. Ben Olson, the nation's top QB prospect 10 years ago, left BYU for a mission following his redshirt year. After a coaching change at the school, Olson transferred to UCLA and never quite materialized because of injuries and ineffectiveness.
Then there's John Beck and Max Hall, also former Cougars who served missions and now play quarterback in the NFL.
It can be done, Young said. And just how genuine is the connection he feels to Mangum?
"When he comes back," Young said, "I'd come personally coach him if it would help."
Service as a priority
Balance is the big thing. It's obvious to a faraway football legend like Young -- and those closest to Mangum.
Mangum possesses a set of skills rare, if not nonexistent, among the other Under Armour All-Americans.
He sings in the choir at school and plays the cello. He's learning the guitar. He is a straight-A student and Eagle Scout. Yes, he said, he can build a fire from wood and kindling.
"He handles himself like he's about 25 years old," said Peterson, his high school coach.
Mangum's mother said she's most proud of how Tanner views his place in society. At an age when many young adults remain self-focused, Tanner feels a calling to serve others. He's divinely guided, Karen Mangum said.
"He understands that the world doesn't revolve around him," Peterson said. "That's who he is in life and in football."
And the other interests make Mangum a better football player.
"I use the lessons I learn in football and apply them in other areas," Mangum said, "and vice versa."
When the hype began to get heavy last summer, Mangum never reconsidered his decision, made some six years ago, to serve. According to his coach, he was unfazed.
"He's so deeply grounded as a young man," Peterson said, "I saw no change whatsoever."
Mangum credits his family for the balance between faith and football. His father, Michael, served a mission in Quebec. In addition to Parker, 27, his brother Madison is serving now in Texas. His sister Meredith played soccer at Boise State, and his sister Abby is a budding athlete, too, at 13.
"I've been blessed with a family that has taught me the importance of priorities," Mangum said. "It's given me a good understanding that football isn't everything, and that it's not going to last forever."
Mitch Sherman is a senior writer for ESPN.com. He can be reached at mshermanespn@gmail.com.
Follow Mitch Sherman on Twitter: @mitchsherman