Last month, two Air Force officers drove through a snowstorm in Boston, looking for any indoor field so they could have a football workout after a long day of serving their country.

One of them was an All-American cornerback a couple years ago. The other a college receiver with measurables that match up well with many of the players who will be drafted later this month.

In that snowstorm, Reggie Rembert and Spencer Armstrong eventually found a field at Harvard. They've been there before, often working out on a field alongside the women's lacrosse team.

"We got a bunch of evil looks," Armstrong says.

This is the routine for Rembert and Armstrong. They work their jobs with the United States Air Force during the day, and desperately keep the door to their NFL dreams pried open at night. They know and understand why they haven't been signed by a NFL team yet. All service academy players with pro dreams eventually learn about the obstacles, most notably the minimum two years of active duty that they have to do after graduation.

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Their big chance to impress NFL teams comes Sunday and Monday at Cowboys Stadium at the NFL's super regional combine. All 32 teams will be represented at the event, which has most of the same drills as the more well-known NFL scouting combine in Indianapolis. Rembert, Armstrong and two other younger former Air Force players, Alex Means and Asher Clark, are among the 218 players who were invited. So were former Army linebacker Josh McNary and Navy running back Gee Gee Greene. Service academy players don't always get this kind of chance.

"All I need is a shot," Rembert said. "I've been busting my tail for two years for this opportunity."

Service academy players don't go to Army, Navy or Air Force just to play football. This fact is reinforced to them constantly. They are there to become military officers. The tradeoff is pretty good though. They have guaranteed jobs making pretty good money upon graduation.

Rembert didn't necessarily go to Air Force figuring he'd have a shot to play in the NFL some day. He went in large part because that and Navy were his only FBS offers. He was overlooked because he was just 5-foot-8. He went on to have an outstanding career and by the end, his pro dreams weren't so outlandish.

Rembert was one of 22 players on the AFCA All-American first-team offense and defense in 2010. And 21 of them have been on a NFL roster.

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Rembert, who was also a third-team Associated Press All-American selection as a senior, hoped to get signed by a NFL team and put on the reserve-military list for two years. Air Force Academy graduates have to serve on active duty at least two years, then can apply for the "Palace Chase" program to turn the rest of their commitment into reserve duty. That's what happened with defensive lineman Ben Garland, who played with Rembert at Air Force and was signed by the Denver Broncos. After two years on the reserve list, Garland was part of Denver's practice squad last year. After Rembert's college career ended, he got some preliminary interest from teams, but no contract.

He spent a year as a graduate assistant coach at Air Force, then was assigned to Hanscom Air Force Base near Boston. Rembert, a second lieutenant who is a project manager on early warning radar upgrade, gets up at 6 a.m. to get to work by 8. Many days over the winter it was dark when he left work, but he always dragged himself to a workout.

NFL teams didn't see that. They don't know that Rembert considers himself a homebody these days because he spends his free time staying in shape, preparing for his chance to impress. He makes it clear he enjoys the Air Force and is proud to serve his country. But he also wants to play in the NFL. He hopes teams notice a former All-American who has kept pursing that dream for two years when it would have been easy to quit.

"I hope teams look at that and say, 'This is a guy who doesn't give up,'" Rembert said.

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