Chicago Bears quarterback Sid Luckman was one of 19 men (out of 28) from his team's 1943 championship squad to leave for the war the following year. While Luckman fought at Normandy, his coach George Halas was the "welfare and recreation officer" for the 7th Fleet in the Pacific. He reportedly sent orders to his old team via telegram.

At 5-foot-7 and 166 pounds, LeBaron became known as the "Littlest General." But the nickname had nothing to do with his College Football Hall of Fame career, in which he started at quarterback, safety and punter for the University of the Pacific. He earned the nickname after serving in the Korean War.

After being drafted by the Washington Redskins in 1950, LeBaron played in two Redskins preseason games -- then entered the Korean War as a second lieutenant with the Marine Corps Reserves. He was wounded twice during his nine months in Korea and was decorated with a Purple Heart. He also was awarded the Bronze Star and the Letter of Commendation.

LeBaron returned from Korea in 1952 to play seven seasons with the Redskins and another four with the Dallas Cowboys. In fact, he was the first starting quarterback in the history of "America's Team" (of course, they weren't known as "America's Team" just yet).

After being drafted by the Pittsburgh Steelers in 1968 and playing one season, Bleier was drafted into the Army and shipped to Vietnam with the 196th Light Infantry Brigade in May of 1969. He was later awarded the Purple Heart and the Bronze Star -- but also left Southeast Asia with a load of shrapnel in his right leg, which is why doctors told him he would never play football again.

But Bleier did play again, returning to the Steelers in 1971 as Franco Harris' blocking fullback and playing on four Super Bowl-winning teams in 10 more NFL seasons.

"For me, to have someone yell at you was second nature," Bleier once said. "In combat, as we have come to learn, when you're put in harm's way, there is a chance of permanent injury. There might not be a tomorrow, and that is always the question that lingers in one's mind. Will I get back safely? Will I be able to survive this combat? In football, there will always be next week."

"Concrete Charlie" a member of the Pro Football Hall of Fame had an illustrious career as a two-way player for the Philadelphia Eagles from 1949 to 1962.

"I'm proud to be an American, home of the free," says Bednarik, who had a long and decorated career in the Army. "This is the greatest place on Earth."

The Bethlehem, Pa., native was drafted into the Army at 18, and then sent to gunnery school in the midst of World War II. Bednarik served with the 467th Bomb Group in the Eighth Air Force, flying 30 missions over Germany in a B-24 Liberation Bomber and was decorated with the Air Medal, four Oak Leaf Clusters and the European-African-Middle Eastern Campaign Ribbon, with five Battle Stars.

"Well, you learn a lot when you are in that situation. You're being shot at. I was just a kid. I had to learn how to survive and to work with my team," he said. "We did that. We survived. It was brutal. I'm thankful to be here to enjoy my life."

George McAfee, right, established himself as a star player for the Chicago Bears in the 1940s, dominating as a runner, receiver, and punt returner. McAfee's NFL career was interrupted by World War II, when he enlisted in the Navy. He was inducted into the Pro Football Hall of Fame in 1966.

Wilson enlisted in the Navy and was in the Atlantic and Pacific theaters during World War II. He went on to found the Buffalo Bills and was an influential AFL owner. Wilson, a key figure in the 1970 AFL-NFL merger, was enshrined in the Pro Football Hall of Fame in 2009 after building the small-market Bills into one of the sport's real success stories.

There aren't many truly American tales quite as impressive as Roger Staubach's: Naval Academy; Heisman Trophy; tour of duty in Vietnam; Super Bowl hero for the Dallas Cowboys, "America's Team", of course -- and Pro Football Hall of Fame. Not to mention that he went into business after football and sold his company for hundreds of millions of dollars.

Special nod here goes to NFL.com's own Gil Brandt. As vice president of the Cowboys when they drafted Staubach in 1964 -- five years before he could start his career because of his military commitment -- Brandt had the idea to ship footballs to Vietnam so the quarterback could keep his throwing arm fresh during his free time.

Staubach resigned his commission in 1969, spent 11 years with the Cowboys, won two Super Bowls and was enshrined in the Hall of Fame in 1985.

Clyde "Bulldog" Turner was drafted out of Hardin-Simmons University by the Chicago Bears in the first round of the 1940 draft. At a time when players from small schools were rarely noticed by the NFL, Turner was a dominant center and linebacker for the Bears, earning four Pro Bowls and seven first-team all-pro selections.

He was drafted into the Army towards the end of World War II in 1945.

Turner was inducted into the Pro Football Hall of Fame in 1966.

He wasn't called "The Golden Boy" for nothing. Hornung has led a charmed life in many ways. For starters, he remains the only person ever to win the Heisman Trophy while playing for a team with a losing record, in 1956 with Notre Dame.

Hornung was called into active duty in the Army in 1961, five years into his Hall of Fame career with the Green Bay Packers. Fortunately for Hornung, his boss -- Vince Lombardi -- was friends with President John F. Kennedy. So Lombardi was able to arrange for his versatile threat -- halfback and kicker -- to receive weekend passes in the fall in order to play for the Packers on Sundays.

Not a bad gig.

Hornung led the NFL in scoring for the third consecutive season in 1961. And during Christmas leave from the Army, he set an NFL record by scoring 19 points in the NFL Championship Game, helping the Packers crush the Giants, 37-0.

Chad Hennings is a former NFL football defensive tackle. Drafted by the Dallas Cowboys in 1988 although he did not play until 1992 after he left the U.S. Air Force. He played for 9 seasons and won three Super Bowls.

Bryce Fisher is a former NFL defensive lineman. He was drafted by the Buffalo Bills in 1999 but did not play until 2001, after completing his two-year Air Force commitment. He also played for the St. Louis Rams, Seattle Seahawks, and the Tennessee Titans.

When the Detroit Lions took Campbell in the seventh round of the 2008 NFL Draft, he became the first Army player selected in over a decade. But Campbell went to serve his country for two years before joining the Lions in 2010. He started the season on the practice squad but was activated in November and made three tackles in three games as a defensive back.

"When you walk on to (Army's football) field, you see a sign that says, 'I want an officer for a secret and dangerous mission. I want a West Point football player.' The trust you have to have that the guy next to you is going to get his job done and the discipline that the Academy establishes in each and every cadet -- that carries over to the football field. There are so many times here that you just want to call it quits and you don't think you can go on, but you keep going and never look back knowing that tomorrow is another day."

Many NFL players have served in the military. What separates Pat Tillman from the rest isn't his tragic death in 2004. It's the fact that he's the only one to give up a multimillion-dollar contract to serve his country. And his decision to enlist in the Army Rangers in 2002 was purely voluntary, having been motivated by the 9/11 terrorist attacks on the United States. While his NFL experience pales in comparison to his experience in Afghanistan and the tragedy that ensued, it's not wrong to wonder what could have been if Tillman never left the gridiron. When he enlisted, Tillman was just 25 years old and entering his fifth NFL season. The safety already had one All-Pro season under his belt in Arizona and developed a reputation as an intense and active player. How good could he have been? Sadly, we'll never know.

Mike Anderson is a former NFL running back and Marine. He was drafted by the Denver Broncos in 2000 and received the NFL Offensive Rookie of the Year Award. He played a total of 8 season, six for the Denver Broncos and two for the Baltimore Ravens.

Villanueva played offensive tackle, defensive lineman and wide receiver while at Army. After starting every game at left tackle during his junior season, the 6-foot-9 Villanueva was asked to play wide receiver as a senior in 2009 (he caught 34 passes for 522 yards and five touchdowns).

Villanueva went undrafted in 2010, had a tryout with the Cincinnati Bengals, and then spent four years as an active member of the Army, serving in three tours in Afghanistan. He worked out at a regional combine in 2014 and signed with the Philadelphia Eagles as a defensive end. Shortly after being released by the Eagles, Villaneuva was signed by the Pittsburgh Steelers and assigned to the practice squad. He was elevated to the active roster in 2015, and started 10 games that year at left tackle.

Nate Boyer is a former NFL long snapper for the Seattle Seahawks and United States Army Green Beret. He was signed by the Seahawks in 2015 as an undrafted free agent after playing college football at the University of Texas as a walk-on. Boyer was honorably discharged after serving six years and multiple tours in Iraq and Afghanistan.

Joe Cardona is a long snapper for the New England Patriots after being drafted in the fifth round of the 2015 NFL Draft. Cardona graduated from the U.S. Naval Academy where he played college football and is an officer in the U.S. Naval Reserve. He played for the Patriots when they won Super Bowl LI against the Atlanta Falcons.